4.1. Therapeutic indications

Female patients:

• For all female patients aged under 55 years: For the treatment of generalised, partial or other epilepsy only when there is no other effective or tolerated treatment.

• For all female patients aged over 55 years: For the treatment of generalised, partial or other epilepsy.

Male patients:

• For all male patients aged under 55 years initiating treatment with valproate: For the treatment of generalised, partial or other epilepsy only when there is no other effective or tolerated treatment.

• For all male patients established on treatment with valproate or male patients aged over 55 years: For the treatment of generalised, partial or other epilepsy.

4.2. Posology and method of administration

Convulex capsules are for oral administration.

Daily dosage requirements vary according to age and body weight.

Convulex capsules may be given twice daily.

Female children and women of childbearing potential aged under 55 years

No new female patients aged under 55 years should be initiated on valproate unless two specialists independently consider and document that there is no other effective or tolerated treatment (see sections 4.3, 4.4 and 4.6).

Valproate must be supervised by a specialist experienced in the management of epilepsy.

Valproate should not be prescribed in female children and women of childbearing potential aged under 55 years unless two specialists independently consider and document that there is no other effective or tolerated treatment (see sections 4.3, 4.4 and 4.6).

Where possible, existing female children and women of childbearing potential aged under 55 years should be switched to another treatment unless two specialists independently consider and document there is no other effective or tolerated treatment. For those continuing to receive valproate, the benefits and risks of valproate should be carefully reconsidered at regular treatment reviews, at least annually (see section 4.4).

Valproate must be prescribed and dispensed according to the Valproate Pregnancy Prevention Programme (sections 4.3 and 4.4).

Valproate should preferably be prescribed as monotherapy and at the lowest effective dose, if possible as a prolonged release formulation. The daily dose should be divided into at least two single doses (see section 4.6).

Male patients aged under 55 years

No new male children or men aged under 55 years should be initiated on valproate unless two specialists independently consider and document that there is no other effective or tolerated treatment or the risk of infertility or potential risk of testicular toxicity are not applicable (see sections 4.4 and 4.6).

The specialist should discuss and complete the risk acknowledgement form with the patient and/or carer at initiation to ensure all male children and men aged under 55 years are aware of the risk of infertility in males (see sections 4.4, 4.6 and 4.8) and of the data available showing testicular toxicity in animals exposed to valproate and the uncertain clinical relevance (see section 5.3).

Posology

Monotherapy:

Usual requirements are as follows:

a) Adults

Dosage should start at 600 mg daily, followed by gradual increases (approx. 300 mg) at three day intervals until control is achieved. This is generally within the dosage range 1000 mg to 2000 mg per day, i.e. 20-30 mg/kg body weight. Where adequate control is not achieved within this range, the dose may be further increased up to 2500 mg per day.

b) Elderly Patients

Although the pharmacokinetics of valproate are modified in the elderly, they have limited clinical significance and dosage should be determined by seizure control. The volume of distribution is increased in the elderly and because of decreased binding to serum albumin, the proportion of free drug is increased. This will affect the clinical interpretation of plasma valproic acid levels.

c) Paediatric population

Children over 20kg

Initial dosage is usually not more than 400mg/day (irrespective of weight) with spaced increases until control is achieved; this is usually within the range 20-30mg/kg body weight per day. Where adequate control is not achieved within this range the dose may be increased to 35mg/kg body weight per day. In children requiring doses higher than 40mg/kg/day, clinical chemistry and haematological parameters should be monitored.

Children under 20kg

Initial dosage should be 20mg/kg of body weight per day; in severe cases this may be increased but only in patients in whom plasma valproic acid levels can be monitored. In children requiring doses higher than 40mg/kg/day, clinical chemistry and haematological parameters should be monitored.

d) In patients with renal insufficiency

It may be necessary in patients with renal insufficiency to decrease the dosage, or to increase the dosage in patients on haemodialysis. Valproate is dialysable (see section 4.9). Dosing should be modified according to clinical monitoring of the patient (see section 4.4).

e) In patients with hepatic insufficiency

Salicylates should not be used concomitantly with valproate since they employ the same metabolic pathway (see also sections 4.4 and 4.8).

Liver dysfunction, including hepatic failure resulting in fatalities, has occurred in patients whose treatment included valproic acid (see sections 4.3 and 4.4).

Salicylates should not be used in children under 16 years (see aspirin/salicylate product information on Reye's syndrome). In addition in conjunction with valproate, concomitant use in children under 3 years can increase the risk of liver toxicity (see section 4.4).

Combined therapy (see section 4.5):

When starting Convulex in patients already on other anticonvulsants, these should be tapered slowly; initiation of Convulex therapy should then be gradual, with target dose being reached after about 2 weeks. In certain cases it may be necessary to raise the dose by 5 to 10mg/kg/day when used in combination with anticonvulsants which induce liver enzyme activity, e.g. phenytoin, phenobarbital and carbamazepine. Once known enzyme inducers have been withdrawn it may be possible to maintain seizure control on a reduced dose of Convulex. When barbiturates are being administered concomitantly and particularly if sedation is observed (particularly in children) the dosage of barbiturate should be reduced.

Optimum dosage is mainly determined by seizure control and routine measurement of plasma levels is unnecessary. However, a method for measurement of plasma levels is available and may be helpful where there is poor control or side effects are suspected (see section 5.2).

4.3. Contraindications

Convulex is contraindicated in the following situations:

- in pregnancy, unless two specialists independently consider and document that there is no other effective or tolerated treatment (see section 4.4 and 4.6).

- in women of childbearing potential aged under 55 years, unless two specialists independently consider and document that there is no other effective or tolerated treatment and the conditions of the pregnancy prevention programme are fulfilled (see section 4.4 and 4.6).

- hypersensitivity to valproic acid or any other excipients listed in section 6.1.

- active liver disease, or personal or family history of severe hepatic dysfunction, especially drug related.

- patients with known urea cycle disorders (see section 4.4).

- porphyria.

- patients known to have mitochondrial disorders caused by mutations in the nuclear gene encoding the mitochondrial enzyme polymerase γ (POLG), e.g. Alpers-Huttenlocher Syndrome, and in children under two years of age who are suspected of having a POLG-related disorder (see section 4.4).

- patients with uncorrected systemic primary carnitine deficiency (see section 4.4).

4.4. Special warnings and precautions for use

Female children, women of childbearing potential aged under 55 years and pregnant women:

Pregnancy Prevention Programme

Valproate has a high teratogenic potential and children exposed in utero to valproate have a high risk (11%) for congenital malformations and neurodevelopmental disorders (30-40%) which may lead to permanent disability (see section 4.6).

Valproate must only be initiated by two specialists who independently consider and document that there is no other effective or tolerated treatment.

Convulex is contraindicated in the following situations:

- in pregnancy unless two specialists independently consider and document that there is no other effective or tolerated treatment (see sections 4.3 and 4.6).

- in women of childbearing potential aged under 55 years, unless two specialists independently consider and document that there is no other effective or tolerated treatment and the conditions of the pregnancy prevention programme are fulfilled (see sections 4.3 and 4.6).

Conditions of Pregnancy Prevention Programme:

The specialist must ensure that

- Individual circumstances should be evaluated in each case, involving the patient in the discussion, to support her engagement, discuss therapeutic options and ensure her understanding of the risks and the measures needed to minimise the risks.

- the potential for pregnancy is assessed for all female patients.

- the patient has understood and acknowledged the risks of congenital malformations and neurodevelopmental disorders which may lead to permanent disability, including the magnitude of these risks for children exposed to valproate in utero.

- the patient understands the need to undergo pregnancy testing prior to initiation of treatment and during treatment, as needed.

- the patient is counselled regarding contraception, and that the patient is capable of complying with the need to use effective contraception (for further details please refer to subsection contraception of this boxed warning), without interruption during the entire duration of treatment with valproate.

- the patient understands the need for regular (at least annual) review of treatment by a specialist experienced in the management of epilepsy.

- the patient understands the need to consult her general practitioner (GP) for referral to a specialist as soon as she is planning a pregnancy to ensure timely discussion and switching to another treatment prior to conception, and before contraception is discontinued.

- the patient understands the need to urgently consult her GP for urgent referral to a specialist in case of pregnancy.

- the patient has received the patient guide.

- the patient has acknowledged that she has understood the hazards and necessary precautions associated with valproate use (Annual Risk Acknowledgement Form).

These conditions also apply to women who are not currently sexually active unless the specialist considers that there are compelling reasons to indicate that there is no risk of pregnancy.

Female children

- The specialist must ensure that parents/caregivers of female children understand the need to contact their GP once the female child using valproate experiences menarche. Their GP will refer the patient back to the specialist.

- The specialist must ensure that parents/caregivers of female children who have experienced menarche are provided with comprehensive information about the risks of congenital malformations and neurodevelopmental disorders which may lead to permanent disability including the magnitude of these risks for children exposed to valproate in utero.

- In patients who experienced menarche, the prescribing specialist must reassess the need for valproate therapy annually and consider other treatment options. If valproate is the only effective and tolerated treatment, the need for using effective contraception and all other conditions of pregnancy prevention programme should be discussed. Every effort should be made by the specialist to switch the female children to another treatment before they reach menarche.

Pregnancy test

Pregnancy must be excluded before start of treatment with valproate. Treatment with valproate must not be initiated in women of child bearing potential without a negative pregnancy test (plasma pregnancy test) result, confirmed by a health care provider, to rule out unintended use in pregnancy.

Contraception

Women of childbearing potential who are prescribed valproate must use effective contraception, without interruption during the entire duration of treatment with valproate. These patients must be provided with comprehensive information on pregnancy prevention and should be referred for contraceptive advice if they are not using effective contraception. At least one effective method of contraception (preferably a user independent form such as an intra-uterine device or implant) or two complementary forms of contraception including a barrier method should be used. Individual circumstances should be evaluated in each case, when choosing the contraception method involving the patient in the discussion, to support her engagement and compliance with the chosen measures. Even if she has amenorrhea she must follow all the advice on effective contraception.

Oestrogen-containing products

Concomitant use with oestrogen-containing products, including oestrogen-containing hormonal contraceptives, may potentially result in decreased valproate efficacy (see section 4.5). Prescribers should monitor clinical response (seizure control) when initiating or discontinuing oestrogen-containing products.

On the opposite, valproate does not reduce efficacy of hormonal contraceptives.

Annual treatment reviews by a specialist

The specialist should at least annually review whether valproate is the most suitable treatment for the patient. The specialist should discuss and complete the annual risk acknowledgement form with the patient and/or carer at initiation and during each annual review and ensure that the patient has understood its content.

Pregnancy planning

For the indication epilepsy, if a woman is planning to become pregnant, a specialist experienced in the management of epilepsy, must reassess valproate therapy and consider other treatment options. Every effort should be made to switch to an appropriate treatment prior to conception, and before contraception is discontinued (see section 4.6). If switching is not possible, the woman should receive further counselling regarding the valproate risks for the unborn child to support her informed decision making regarding family planning.

In case of pregnancy

If a woman using valproate becomes pregnant, she must immediately contact her GP to be referred to a specialist to re-evaluate treatment with valproate and consider switching to other treatment options. The patients with a valproate exposed pregnancy and their partners should be referred by their GP to a specialist experienced in teratology for evaluation and counselling regarding the exposed pregnancy (see section 4.6).

Pharmacist must ensure that

- the patient card is provided with every valproate pack dispensing and that the patients understand its content.

- the patients are advised not to stop valproate medication and to immediately contact their GP to be referred to a specialist in case of planned or suspected pregnancy.

Educational materials

In order to assist healthcare professionals and patients in avoiding exposure to valproate during pregnancy, the Marketing Authorisation Holder has provided educational materials to reinforce the warnings and provide guidance regarding use of valproate in women of childbearing potential and the details of the pregnancy prevention programme. A patient guide and patient card should be provided to all women of childbearing potential using valproate.

An annual risk acknowledgement form needs to be discussed and completed with the patient and/or carer at time of treatment initiation and during each annual review of valproate treatment by the specialist.

Valproate therapy should only be continued after a reassessment of the benefits and risks of the treatment with valproate for the patient by a specialist experienced in the management of epilepsy.

Male children and men

All male patients and/or carers should be made aware of the potential risk to children born to men treated with valproate in the 3 months before conception (see also section 4.6), of the risk of infertility in men (see sections 4.2, 4.6 and 4.8) and of the data available showing testicular toxicity in animals exposed to valproate and the uncertain clinical relevance (see section 5.3).

A retrospective observational study suggests an increased risk of neuro-developmental disorders (NDDs) in children born to men treated with valproate in the 3 months prior to conception compared to those born to men treated with lamotrigine or levetiracetam (see section 4.6).

As a precautionary measure, GPs and specialists should inform male patients about this potential risk (see section 4.6) and recommend the need for male patients and their female partner to use effective contraception, while using valproate and for at least 3 months after treatment discontinuation.

Male patients should not donate sperm during treatment or for at least 3 months after treatment discontinuation.

Male patients treated with valproate should be regularly reviewed by their GP or specialist. For male patients planning to conceive a child, the specialist should consider and discuss other suitable treatment options with the male patients. Individual circumstances should be evaluated in each case.

Educational materials are available for healthcare professionals and male patients. A patient guide should be provided to male patients using valproate.

For males aged under 55 years, at initiation of treatment, the specialist should discuss and complete the risk acknowledgement form with the patient and/or carer at initiation to ensure all male children and men aged under 55 years are aware of the potential risk to offspring and of the risk of infertility in males and testicular toxicity data in animals.

Liver dysfunction:

Conditions of occurrence:

Severe liver damage, including hepatic failure sometimes resulting in fatalities, has been reported. Experience in epilepsy has indicated that patients most at risk are infants, especially in cases of multiple anticonvulsant therapy, are infants and in particular young children under the age of 3 and those with severe seizure disorders, organic brain disease, and (or) congenital metabolic disorders including mitochondrial disorders such as carnitine deficiency, urea cycle disorders, POLG mutations (see sections 4.3 and 4.4) or degenerative disease associated with mental retardation.

After the age of 3, the incidence of occurrence is significantly reduced and progressively decreases with age.

The concomitant use of salicylates should be avoided in children under 3 due to the risk of liver toxicity (see also section 4.5). Additionally, salicylates should not be used in children under 16 years (see aspirin/salicylate product information on Reye's syndrome).

Monotherapy is recommended in children under the age of 3 years when prescribing valproate, but the potential benefit of valproate should be weighed against the risk of liver damage or pancreatitis in such patients prior to initiation of therapy (see sections 4.4 and 4.5).

In most cases, such liver damage occurred during the first 6 months of therapy, the period of maximum risk being 2-12 weeks.

Suggestive signs:

Clinical symptoms are essential for early diagnosis. In particular the following conditions, which may precede jaundice, should be taken into consideration, especially in patients at risk:

- non specific symptoms, usually of sudden onset, such as asthenia, malaise, anorexia, lethargy, oedema and drowsiness, which are sometimes associated with repeated vomiting and abdominal pain.

- in patients with epilepsy, recurrence of seizures.

These are an indication for immediate withdrawal of the drug.

Patients (or their family for children) should be instructed to report immediately any such signs to a physician should they occur. Investigations including clinical examination and biological assessment of liver function should be undertaken immediately.

Detection:

Liver function should be measured before and then periodically monitored during the first 6 months of therapy, especially for patients at risk and those with a prior history of liver disease. Upon changes in concomitant medicinal products (dose increase or additions) that are known to impact the liver, liver monitoring should be restarted as appropriate (see section 4.5).

Amongst usual investigations, tests which reflect protein synthesis, particularly prothrombin rate, are most relevant.

Confirmation of an abnormally low prothrombin rate, particularly in association with other biological abnormalities (significant decrease in fibrinogen and coagulation factors; increased bilirubin level and raised transaminases) requires cessation of valproate therapy.

As a matter of precaution and in case they are taken concomitantly salicylates should also be discontinued since they employ the same metabolic pathway.

As with most antiepileptic drugs, increased liver enzymes are common, particularly at the beginning of therapy; they are also transient.

More extensive biological investigations (including prothrombin rate) are recommended in these patients; a reduction in dosage may be considered when appropriate and tests should be repeated as necessary.

Patients with known or suspected mitochondrial disease

Valproate may trigger or worsen clinical signs of underlying mitochondrial diseases caused by mutations of mitochondrial DNA as well as the nuclear encoded POLG gene. In particular, valproate-induced acute liver failure and liver-related deaths have been reported at a higher rate in patients with hereditary neurometabolic syndromes caused by mutations in the gene for the mitochondrial enzyme polymerase γ (POLG), e.g. Alpers-Huttenlocher Syndrome.

POLG-related disorders should be suspected in patients with a family history or suggestive symptoms of a POLG-related disorder, including but not limited to unexplained encephalopathy, refractory epilepsy (focal, myoclonic), status epilepticus at presentation, developmental delays, psychomotor regression, axonal sensorimotor neuropathy, myopathy, cerebellar ataxia, opthalmoplegia, or complicated migraine with occipital aura. POLG mutation testing should be performed in accordance with current clinical practice for the diagnostic evaluation of such disorders (see section 4.3).

Urea cycle disorders and risk of hyperammonaemia

When a urea cycle enzymatic deficiency is suspected, metabolic investigations should be performed prior to treatment because of the risk of hyperammonaemia with valproate (see sections 4.3 and 4.4).

Patients at risk of hypocarnitinaemia

Valproate administration may trigger occurrence or worsening of hypocarnitinaemia that can result in hyperammonaemia (that may lead to hyperammonemic encephalopathy). Other symptoms such as liver toxicity, hypoketotic hypoglycaemia, myopathy including cardiomyopathy, rhabdomyolysis, Fanconi syndrome have been observed, mainly in patients with risk factors for hypocarnitinaemia or pre-existing hypocarnitinaemia. Patients at increased risk for symptomatic hypocarnitinaemia when treated with valproate include patients with metabolic disorders including mitochondrial disorders related to carnitine (see section 4.4), impairment in carnitine nutritional intake, patients younger than 10 years old, concomitant use of pivalate-conjugated medicines or of other antiepileptics.

Patients should be warned to report immediately any signs of hyperammonaemia such as ataxia, impaired consciousness, vomiting. Carnitine supplementation should be considered when symptoms of hypocarnitinaemia are observed.

Patients with systemic primary carnitine deficiency and corrected for hypocarnitinaemia may only be treated with valproate if the benefits of valproate treatment outweigh the risks in these patients and there is no therapeutic alternative. In these patients, carnitine monitoring should be implemented.

Patients with an underlying carnitine palmitoyltransferase (CPT) type II deficiency should be warned of an increased risk of rhabdomyolysis developing with valproate therapy. Carnitine supplementation should be considered in these patients. See also sections 4.5, 4.8 and 4.9.

Pancreatitis

Pancreatitis, which may be severe and result in fatalities, has been very rarely reported. Patients experiencing nausea, vomiting or acute abdominal pain should have a prompt medical evaluation (including measurement of serum amylase).Young children are at particular risk; this risk decreases with increasing age. Severe seizures and severe neurological impairment with concomitant anticonvulsant therapy may be risk factors. Hepatic failure with pancreatitis increases the risk of fatal outcome. In case of pancreatitis, valproate should be discontinued.

Patients with a history of pancreatitis have to be closely monitored (see section 4.8).

Severe Cutaneous Adverse Reactions and Angioedema

Severe Cutaneous Adverse Reactions (SCARs) such as Stevens-Johnson Syndrome (SJS), Toxic Epidermal Necrolysis (TEN) and Drug reaction with eosinophilia and systemic symptoms (DRESS), erythema multiforme and angioedema, have been reported in association with valproate treatment. Patients should be informed about the signs and symptoms of serious skin manifestations and monitored closely. In case signs of SCARs or angioedema are observed, prompt assessment is needed, and treatment must be discontinued if diagnosis of SCARs or angioedema is confirmed.

Aggravated convulsions

As with other antiepileptics, some patients may experience, instead of an improvement, a reversible worsening of convulsion frequency and severity (including status epilepticus), or the onset of new types of convulsions, with valproate. In case of aggravated convulsions, the patients should be advised to consult their physician immediately (see section 4.8).

Suicidal ideation and behaviour

Suicidal ideation and behaviour have been reported in patients treated with antiepileptic agents in several indications. A meta-analysis of randomised placebo controlled trials of anti-epileptic drugs has also shown a small increased risk of suicidal ideation and behaviour. The mechanism of this risk is not known and the available data do not exclude the possibility of an increased risk for valproic acid.

Therefore patients should be monitored for signs of suicidal ideation and behaviours and appropriate treatment should be considered. Patients (and caregivers of patients) should be advised to seek medical advice should signs of suicidal ideation or behaviour emerge.

Carbapenem agents: The concomitant use of valproate and carbapenem agents is not recommended.

Precautions

Haematological investigations: Blood tests (blood cell count, including platelet count, bleeding time and coagulation tests) are recommended prior to initiation of therapy or before surgery, and in case of spontaneous bruising or bleeding (see section 4.8). Caution should be exercised if clearly prolonged thromboplastin time (reduced Quick's time) is associated with other altered laboratory results such as decreased fibrinogen level, decreased coagulation factors, increased bilirubin or increased hepatic enzymes.

Renal insufficiency: In patients with renal insufficiency, it may be necessary to decrease dosage. As monitoring of plasma concentrations may be misleading, dosage should be adjusted according to clinical monitoring (see sections 4.2 and 5.2).

Systemic lupus erythematosus: Although immune disorders have only rarely been noted during the use of valproate, the potential benefit of valproate should be weighed against its potential risk in patients with systemic lupus erythematosus (see also section 4.8).

Weight gain: Valproate very commonly causes weight gain, which may be marked and progressive. Patients should be warned of the risk of weight gain at the initiation of therapy and appropriate strategies should be adopted to minimise it (see section 4.8).

Diabetic patients: Valproate is eliminated mainly through the kidneys, partly in the form of ketone bodies; this may give false positives in the urine testing of possible diabetics.

Infants younger than 3 years

In infants younger than 3 years monotherapy with valproate is recommended. Prior to therapy start the benefit of antiepileptic treatment has to be weighed against the risk of liver damage or pancreatitis. Concomitant use of salicylates has to be avoided in these patients due to the risk of hepatotoxicity.

Alcohol

Alcohol intake is not recommended during treatment with valproate.

4.5. Interaction with other medicinal products and other forms of interaction

Effects of Valproate on other drugs

Antipsychotics, MAO inhibitors, antidepressants and benzodiazepines

Valproate may potentiate the effect of other psychotropics such as antipsychotics, MAO inhibitors, antidepressants and benzodiazepines; therefore, clinical monitoring is advised and dosage of other psychotropics should be adjusted when appropriate.

In particular, a clinical study has suggested that adding olanzapine to valproate or lithium therapy may significantly increase the risk of certain adverse events associated with olanzapine e.g. neutropenia, tremor, dry mouth, increased appetite and weight gain, speech disorder and somnolence.

Lithium

Valproate does not effect serum concentrations of lithium.

Olanzapine

Valproic acid may decrease the olanzapine plasma concentration.

Phenobarbital

Valproate increases phenobarbital plasma concentrations (due to inhibition of hepatic catabolism) and sedation may occur, particularly in children. Therefore, clinical monitoring is recommended throughout the first 15 days of combined treatment with immediate reduction of phenobarbital doses if sedation occurs and determination of phenobarbital plasma levels when appropriate.

Primidone

Valproate increases primidone plasma levels with exacerbation of its adverse effects (such as sedation); these signs cease with long term treatment. Clinical monitoring is recommended especially at the beginning of combined therapy with dosage adjustment when appropriate.

Phenytoin

Valproate decreases phenytoin total plasma concentration. Moreover valproate increases phenytoin free form with possible overdosage symptoms (valproic acid displaces phenytoin from its plasma protein binding sites and reduces its hepatic catabolism). Therefore clinical monitoring is recommended; when phenytoin plasma levels are determined, the free form should be evaluated.

Carbamazepine

Clinical toxicity has been reported when valproate was administered with carbamazepine as valproate may potentiate toxic effects of carbamazepine. Clinical monitoring is recommended especially at the beginning of combined therapy with dosage adjustment when appropriate.

Lamotrigine

Valproate may reduce lamotrigine metabolism and increase its mean half-life by nearly two-fold. Co-administration of lamotrigine and valproate might increase the risk of rash. Therefore, clinical monitoring is recommended, and dosages should be adjusted (lamotrigine dosage decreased) when appropriate.

Felbamate

Valproic acid may decrease the felbamate mean clearance by up to 16%.

Rufinamide

Valproate may cause plasma levels of rufinamide to increase. This effect depends on valproate plasma levels. Caution should be exercised, especially in children, because this patient group is more likely to be affected by this interaction.

Propofol

Valproate may cause propofol blood concentrations to increase. In case of concomitant use with valproate the dose of propofol has to be reduced.

Zidovudine

Valproate may raise zidovudine plasma concentration leading to increased zidovudine toxicity.

Nimodipine

In patients concomitantly treated with valproate and nimodipine the exposure to nimodipine can be increased by 50%. The nimodipine dose should therefore be decreased in case of hypotension.

Temozolomide

Co-administration of temozolomide and valproate may cause a small decrease in the clearance of temozolomide that is not thought to be clinically relevant.

Clozapine

Concomitant treatment of valproate and clozapine may increase the risk of neutropenia and clozapine-induced myocarditis. If concomitant use of valproate with clozapine is necessary, careful monitoring for both events is required.

Effects of other drugs on Valproate

Antiepileptics

Antiepileptics with enzyme inducing effect (including phenytoin, phenobarbital, carbamazepine) decrease valproic acid plasma concentrations. Dosages should be adjusted according to blood levels in case of combined therapy.

Upon concomitant use of valproate with phenytoin or phenobarbital the plasma levels of valproic acid metabolites may increase. Therefore patients under combined treatment with these substances should be closely monitored for signs or symptoms of hyperammonaemia.

On the other hand, combination of felbamate and valproate may increase valproic acid clearance by 22 – 50% and consequently increase the valproic acid plasma concentration. Valproate dosage should be monitored.

Anti-malaria agents

Mefloquine and chloroquine increase valproic acid metabolism and may lower the seizure threshold; therefore epileptic seizures may occur in cases of combined therapy. Accordingly, the dosage of valproate may need adjustment.

Highly protein-bound agents

In case of concomitant use of valproate and highly protein bound agents (e.g. aspirin), free valproic acid plasma levels may be increased.

Vitamin K-dependent anticoagulants

The anticoagulant effect of warfarin and other coumarin anticoagulants may be increased following displacement from plasma protein binding sites by valproic acid. The prothrombin time should be closely monitored.

Cimetidine or erythromycin

Valproic acid plasma levels may be increased (as a result of reduced hepatic metabolism) in case of concomitant use with cimetidine or erythromycin.

Carbapenem antibiotics (e.g. panipenem, meropenem, imipenem)

Decreases in blood levels of valproic acid have been reported when it is co-administered with carbapenem agents resulting in a 60-100 % decrease in valproic acid levels in about two days. Due to the rapid onset and the extent of the decrease, co-administration of carbapenem agents in patients stabilised on valproic acid is not considered to be manageable and therefore should be avoided (see section 4.4). If treatment with these antibiotics cannot be avoided close monitoring of valproic acid blood levels should be performed.

Rifampicin

Rifampicin may decrease valproic acid blood levels, resulting in a lack of therapeutic effect.

Therefore, valproate dosage adjustment may be necessary if co-administered with rifampicin.

Protease inhibitors

Concomitant use of valproate with protease inhibitors such as lopinavir and ritonavir may cause the levels of valproic acid metabolites to decrease.

Cholestyramine

Cholestyramine may decrease the absorption of valproate.

Oestrogen-containing products, including oestrogen-containing hormonal contraceptives

Oestrogens are inducers of the UDP-glucuronosyl transferase (UGT) isoforms involved in valproate glucuronidation and may increase the clearance of valproate, which would result in decreased serum concentration of valproate and potentially decreased valproate efficacy (see section 4.4). Consider monitoring of valproate serum levels.

On the opposite, valproate has no enzyme inducing effect; as a consequence, valproate does not reduce efficacy of oestroprogestative agents in women receiving hormonal contraception.

Metamizole

Co-administration of valproate with metamizole, which is an inducer of metabolising enzymes including CYP2B6 and CYP3A4 may cause a reduction in plasma concentrations of valproate with potential decrease in clinical efficacy.

Therefore, caution is advised when metamizole and valproate are administered concurrently; clinical response and/or drug levels should be monitored as appropriate.

Methotrexate

Some case reports describe a significant decrease in valproate serum levels after methotrexate administration, with occurrence of seizures. Prescribers should monitor clinical response (seizure control) and consider monitoring valproate serum levels as appropriate.

Other Interactions

Risk of liver damage

The concomitant use of salicylates should be avoided in children under 3 years of age due to the risk of liver toxicity (see section 4.4).

Concomitant use of valproate and multiple anticonvulsant therapy increases the risk of liver damage, especially in young children (see section 4.4).

Concomitant use with cannabidiol increases the incidence of transaminases enzyme elevation. In clinical trials in patients of all ages receiving concomitantly cannabidiol at doses 10 to 25 mg/kg and valproate, ALT increases greater than 3 times the upper limit of normal have been reported in 19% of patients. Appropriate liver monitoring should be exercised when valproate is concomitantly used with other anticonvulsants with potential hepatotoxicity, including cannabidiol, and dose reductions or discontinuation should be considered in case of significant anomalies of liver parameters (see section 4.4).

Newer anti-epileptics (including topiramate and acetazolamide)

Caution is advised when using Convulex in combination with newer anti-epileptics whose pharmacodynamics may not be well established.

Concomitant administration of valproate and topiramate or acetazolamide has been associated with encephalopathy and/or hyperammonaemia. In patients taking these two drugs, careful monitoring of signs and symptoms is advised in particularly at-risk patients such as those with pre-existing encephalopathy.

Pivalate-conjugated medicines

Concomitant administration of valproate and pivalate-conjugated medicines (such as cefditoren pivoxil, adefovir dipivoxil, pivmecillinam and pivampicillin) should be avoided due to increased risk of carnitine depletion (see section 4.4). Patients in whom coadministration cannot be avoided should be carefully monitored for signs and symptoms of hypocarnitinaemia.

Quetiapine

Co-administration of valproate and quetiapine may increase the risk of neutropenia/leucopenia.

4.6. Fertility, pregnancy and lactation

Pregnancy

• Convulex is contraindicated in pregnancy unless two specialists independently consider and document that there is no other effective or tolerated treatment (see section 4.3 and 4.4).

• Convulex is contraindicated for use in women of childbearing potential aged under 55 years, unless two specialists independently consider and document that there is no other effective or tolerated treatment and the conditions of the pregnancy prevention programme are fulfilled (see sections 4.3 and 4.4).

Teratogenicity and Developmental Effects

Pregnancy exposure risk related to valproate

In females, both valproate monotherapy and valproate polytherapy including other anti-epileptics are frequently associated with abnormal pregnancy outcomes. Available data show an increased risk of major congenital malformations and neuro-developmental disorders in both valproate monotherapy and polytherapy compared to the population not exposed to valproate.

Valproate was shown to cross the placental barrier both in animal species and in humans (see section 5.2).

In animals: teratogenic effects have been demonstrated in mice, rats and rabbits (see section 5.3).

Congenital malformations from in utero exposure

Data derived from a meta-analysis (including registries and cohort studies) has shown that 10.73% of children of epileptic women exposed to valproate monotherapy during pregnancy suffer from congenital malformations (95% CI: 8.16 – 13.29). This is a greater risk of major malformations than for the general population, for whom the risk is about 2-3%.

The risk of major congenital malformations in children after in utero exposure to antiepileptic drug polytherapy including valproate is higher than that of anti-epileptic drug polytherapy not including valproate.

This risk is dose-dependent in valproate monotherapy, and available data suggests it is dose-dependent in valproate polytherapy. However, a threshold dose below which no risk exists cannot be established.

Available data show an increased incidence of minor and major malformations. The most common types of malformations include neural tube defects, facial dysmorphia, cleft lip and palate, craniostenosis, cardiac, renal and urogenital defects, limb defects (including bilateral aplasia of the radius), and multiple anomalities involving various body systems.

In utero exposure to valproate may also result in hearing impairment or deafness due to ear and/or nose malformations (secondary effect) and/or to direct toxicity on hearing function. Cases describe both unilateral and bilateral deafness or hearing impairment. Outcomes were not reported for all cases. When outcomes were reported, the majority of the cases did not recover.

In utero exposure to valproate may result in eye malformations (including colobomas, microphthalmos) that have been reported in conjunction with other congenital malformations. These eye malformations may affect vision.

Neuro-developmental disorders from in utero exposure

Data have shown that exposure to valproate in utero can have adverse effects on mental and physical development of the exposed children. The risk of neuro-developmental disorders which may lead to permanent disability (including that of autism) seems to be dose-dependent when valproate is used in monotherapy, but a threshold dose below which no risk exists cannot be established based on available data. When valproate is administered in polytherapy with other anti-epileptic drugs during pregnancy, the risks of neuro-developmental disorders which may lead to permanent disability in the offspring were also significantly increased as compared with those in children from the general population or born to untreated women with epilepsy.

The exact gestational period of risk for these effects is uncertain and the possibility of a risk throughout the entire pregnancy cannot be excluded.

Studies in preschool children exposed in utero to valproate show that up to 30-40% experience delays in their early development such as talking and walking later, lower intellectual abilities, poor language skills (speaking and understanding) and memory problems.

Intelligence quotient (IQ) measured in children (age 6) with a history of valproate exposure in utero was on average 7-10 points lower than those children exposed to other anti-epileptics during pregnancy, although the role of confounding factors related to intellectual disability cannot be excluded. There is evidence in children exposed to valproate that the risk of intellectual impairment may be independent from maternal IQ.

There are limited data on the long term outcomes.

Available data show that children exposed to valproate in utero are at increased risk of autistic spectrum disorder (approximately three-fold) and childhood autism (approximately five-fold) compared with the general study population.

Available data from another population-based study show that children exposed to valproate in utero are at increased risk of developing attention deficit/hyperactivity disorder (ADHD) (approximately 1.5-fold) compared to the unexposed population in the study.

Female children, female adolescents and woman of childbearing potential aged under 55 years (see above and section 4.4)

Oestrogen-containing products

Oestrogen-containing products, including oestrogen-containing hormonal contraceptives, may increase the clearance of valproate, which would result in decreased serum concentration of valproate and potentially decreased valproate efficacy (see section 4.4 and 4.5).

If a woman plans a pregnancy

If a woman is planning to become pregnant, a specialist experienced in the management of epilepsy, must reassess valproate therapy and consider alternative treatment options. Every effort should be made to switch to appropriate alternative treatment prior to conception, and before contraception is discontinued (see section 4.4). If switching is not possible, the woman should receive further counselling regarding the valproate risks for the unborn child to support her informed decision-making regarding family planning.

Pregnant women

Valproate as treatment for epilepsy is contraindicated in pregnancy unless there is no suitable alternative treatment (see sections 4.3 and 4.4).

If a woman using valproate becomes pregnant, she must be immediately referred by her GP to a specialist to consider alternative treatment options.

During pregnancy, maternal tonic clonic seizures and status epilepticus with hypoxia may carry a particular risk of death for mother and the unborn child.

If, despite the known risks of valproate in pregnancy and after careful consideration of alternative treatment, in exceptional circumstances a pregnant woman must receive valproate for epilepsy, it is recommended to:

- Use the lowest effective dose and divide the daily dose of valproate into several small doses to be taken throughout the day.

- The use of a prolonged release formulation may be preferable to other treatment formulations in order to avoid high peak plasma concentrations (see section 4.2).

All patients with a valproate exposed pregnancy and their partners should be referred by their GP to a specialist experienced in teratology for evaluation and counselling regarding the exposed pregnancy. Specialized prenatal monitoring should take place to detect the possible occurrence of neural tube defects or other malformations. Folate supplementation before the pregnancy may decrease the risk of neural tube defects which may occur in all pregnancies. However, the available evidence does not suggest it prevents the birth defects or malformations due to valproate exposure.

Valproate therapy should not be discontinued without a reassessment of the benefits and risks of the treatment with valproate for the patient by a physician experienced in the management of epilepsy.

Risk in the neonate

- Cases of hemorrhagic syndrome have been reported very rarely in neonates whose mothers have taken valproate during pregnancy. This hemorrhagic syndrome is related to thrombocytopenia, hypofibrinogenemia and/or to a decrease in other coagulation factors. Afibrinogenemia has also been reported and may be fatal. However, this syndrome must be distinguished from the decrease of the vitamin-K factors induced by phenobarbital and enzymatic inducers. Therefore, platelet count, fibrinogen plasma level, coagulation tests and coagulation factors should be investigated in neonates.

- Cases of hypoglycaemia have been reported in neonates whose mothers have taken valproate during the third trimester of their pregnancy.

- Cases of hypothyroidism have been reported in neonates whose mothers have taken valproate during pregnancy.

- Withdrawal syndrome (such as, in particular, agitation, irritability, hyper-excitability, jitteriness, hyperkinesia, tonicity disorders, tremor, convulsions and feeding disorders) may occur in neonates whose mothers have taken valproate during the last trimester of their pregnancy.

Breast-feeding

Valproate is excreted in human milk with a concentration ranging from 1% to 10% of total maternal serum levels.

Hematological disorders have been shown in breastfed newborns/infants of treated women (see section 4.8).

A decision must be made whether to discontinue breast-feeding or to discontinue/abstain from Convulex therapy taking into account the benefit of breast feeding for the child and the benefit of therapy for the woman. No adverse effects in the nursing infant have been reported. The decision to allow the patient to breast-feed should be taken with regard to all the known facts.

Fertility

Amenorrhoea, polycystic ovaries and increased testosterone levels have been reported in women using valproate (see section 4.8).

Valproate administration may also impair fertility in men (see sections 4.2, 4.4 and 4.8). Fertility dysfunctions are in some cases reversible at least 3 months after treatment discontinuation. Limited numbers of case reports suggest a dose reduction may improve fertility function. However, in some cases, the reversibility of male infertility was unknown.

Males and potential risk of neuro-developmental disorders in children of fathers treated with valproate in the 3 months prior to conception

A retrospective observational study in 3 Nordic countries suggests an increased risk of neuro-developmental disorders (NDDs) in children (from 0 to 11 years old) born to men treated with valproate as monotherapy in the 3 months prior to conception compared to those born to men treated with lamotrigine or levetiracetam as monotherapy, with a pooled adjusted hazard ratio (HR) of 1.50 (95% CI: 1.09-2.07). The adjusted cumulative risk of NDDs ranged between 4.0% to 5.6% in the valproate group versus between 2.3% to 3.2% in the composite lamotrigine/levetiracetam group. The study was not large enough to investigate associations with specific NDD subtypes and study limitations included potential confounding by indication and differences in follow-up time between exposure groups. The mean follow-up time of children in the valproate group ranged between 5.0 and 9.2 years compared to 4.8 and 6.6 years for children in the lamotrigine/levetiracetam group.

Overall, an increased risk of NDDs in children of fathers treated with valproate in the 3 months prior to conception is possible however the causal role of valproate is not confirmed. In addition, the study did not evaluate the risk of NDDs to children born to men stopping valproate for more than 3 months prior to conception (i.e., allowing a new spermatogenesis without valproate exposure).

As a precautionary measure, GPs and specialists should inform male patients about this potential risk and recommend the need for male patients and their female partner to use effective contraception, while using valproate and for at least 3 months after treatment discontinuation (see section 4.4).

Male patients should not donate sperm during treatment or for at least 3 months after treatment discontinuation.

Male patients treated with valproate should be regularly reviewed by their GP or specialist. For male patients planning to conceive a child, the specialist should consider and discuss other suitable treatment options with the male patients. Individual circumstances should be evaluated in each case.

4.7. Effects on ability to drive and use machines

Use of Convulex may provide seizure control such that the patient may be eligible to hold a driving licence.

Patients should be warned of the risk of transient drowsiness, especially in cases of anticonvulsant polytherapy or association with benzodiazepines (see section 4.5).

4.8. Undesirable effects

The following CIOMS frequency rating is used, when applicable:

Very common:

Common:

Uncommon:

Rare:

Very rare:

Not known:

≥1/10

≥1/100 to <1/10

≥1/1,000 to <1/100

≥1/10,000 to <1/1,000

<1/10,000

Frequency cannot be estimated from the available data

System organ class

Very common

Common

Uncommon

Rare

Not known

Neoplasms benign, malignant and unspecified (incl. cysts and polyps)

myelodysplastic syndrome

Blood and lymphatic system disorders

anaemia, thrombocytopenia

pancytopenia**, leucopenia**

bone marrow dysfunction (including pure red cell aplasia, agranulocytosis, macrocytic anaemia, macrocytosis)

Endocrine disorders

syndrome of inappropriate antidiuretic hormone secretion (SIADH), hyperandrogenaemia (hirsutism, virilism, acne, male alopecia and/or increased androgen level)

hypothyroidism

Metabolism and nutrition disorders

hyponatraemia, weight gain**

hyperammonaemia**, obesity

hypocarnitinaemia

Psychiatric disorders

hallucinations, confusional state, aggression, agitation, disturbance in attention

abnormal behaviour, psychomotor hyperactivity, learning disorder

Nervous system disorders

tremor**

extrapyramidal disorder, stupor**, somnolence**, convulsions, memory impairment, headache, nystagmus,

coma**, ataxia, encephalopathy, lethargy**, reversible parkinsonism, paraesthesia, aggravated convulsions (see section 4.4)

reversible dementia associated with reversible cerebral atrophy, cognitive disorder

Eye disorders

diplopia

Ear and labyrinth disorders

hearing loss

Vascular disorders

haemorrhage

vasculitis

Respiratory, thoracic and mediastinal disorders

pleural effusion (eosinophilic)

Gastrointestinal disorders

nausea

vomiting, gingival disorder (especially gingival hyperplasia), stomatitis, gastralgia, diarrhoea**

pancreatitis, sometimes lethal (see section 4.4)

Hepatobiliary disorders

liver injury (see section 4.4)

Skin and subcutaneous tissue disorders

hypersensitivity reactions, transient and/or dose-related hair loss, nail and nail bed disorders

angioedema, rash, hair disorder (e.g. altered hair texture, change of hair colour, abnormal hair growth)

toxic epidermal necrolysis, Stevens-Johnson syndrome, erythema multiforme, Drug Rash with Eosinophilia and Systemic Symptoms (DRESS syndrome)

hyperpigmentation

Musculoskeletal and connective tissue disorders

decreased bone mineral density**, osteopenia**, osteoporosis and fractures**

systemic lupus erythematosus, rhabdomyolysis

Renal and urinary disorders

urinary incontinence

renal insufficiency

enuresis, tubulo-interstitial nephritis, reversible Fanconi syndrome**

Reproductive system and breast disorders

dysmenorrhoea

amenorrhoea

male infertility, polycystic ovarian syndrome

General disorders and administration site conditions

hypothermia, peripheral oedema

Investigations

coagulation factors decreased**, abnormal coagulation tests**

** Description of selected adverse reactions

Hepato-biliary disorders

Severe liver damage, including hepatic failure sometimes resulting in death, has been reported (see also sections 4.2, 4.3 and 4.4). Increased liver enzymes are common, particularly early in treatment, and may be transient (see section 4.4).

Gastrointestinal disorders (nausea, gastralgia, diarrhoea) frequently occur at the start of treatment. These problems can usually be overcome by taking Convulex capsules with or after food.

Uncommon cases of pancreatitis, sometimes lethal, have been reported (see section 4.4).

Blood and lymphatic system disorders

The blood picture returned to normal when the drug was discontinued.

Isolated reduction of fibrinogen or reversible increase in bleeding time have been reported, usually without associated clinical signs and particularly with high doses (valproate has an inhibitory effect on the second phase of platelet aggregation). Spontaneous bruising or bleeding is an indication for withdrawal of medication pending investigations (see also section 4.6).

Metabolism and nutrition disorders

Cases of isolated and moderate hyperammonaemia without change in liver function tests may occur frequently, are usually transient and should not cause treatment discontinuation. However, they may present clinically as vomiting, ataxia, and increasing clouding of consciousness. Should these symptoms occur Convulex should be discontinued.

Hyperammonaemia associated with neurological symptoms has also been reported. In such cases further investigations should be considered (see sections 4.3 and 4.4).

Weight increase should be carefully monitored since it is a factor for polycystic ovary syndrome (see section 4.4).

Nervous system disorders

Sedation has been reported occasionally, usually when in combination with other anticonvulsants. In monotherapy it occurred early in treatment on rare occasions and is usually transient.

Rare cases of lethargy occasionally progressing to stupor, sometimes with associated hallucinations or convulsions have been reported. Encephalopathy and coma have very rarely been observed. These cases have often been associated with too high a starting dose or too rapid a dose escalation or concomitant use of other anti-convulsants, notably phenobarbital or topiramate. They have usually been reversible on withdrawal of treatment or reduction of dosage.

An increase in alertness may occur; this is generally beneficial but occasionally aggression, hyperactivity and behavioural deterioration have been reported.

Ear and labyrinth disorders

Hearing loss, either reversible or irreversible has been reported; however a cause and effect relationship has not been established.

Musculoskeletal and connective tissue disorders

There have been reports of decreased bone mineral density, osteopenia, osteoporosis and fractures in patients on long-term therapy with medicinal products containing valproate. The mechanism by which valproate affects bone metabolism has not been identified.

Renal and urinary disorders

There have been isolated reports of a reversible Fanconi's syndrome (a defect in proximal renal tubular function giving rise to metabolic acidosis, glycosuria, amino aciduria, phosphaturia, and uricosuria) associated with valproate therapy, but the mode of action is as yet unclear.

Reproductive system and breast disorders

Very rarely gynaecomastia has occurred.

Congenital, familial and genetic disorders

Congenital malformations and developmental disorders (see section 4.4 and section 4.6).

Investigations

Coagulation factors decreased, abnormal coagulation tests (e.g. prothrombin time prolonged, activated partial thromboplastin time prolonged, thrombin time prolonged, INR prolonged).

Paediatric population

The safety profile of valproate in the paediatric population is comparable to adults, but some ADRs are more severe or principally observed in the paediatric population. There is a particular risk of severe liver damage in infants and young children especially under the age of 3 years. Young children are also at particular risk of pancreatitis. These risks decrease with increasing age (see Section 4.4). Psychiatric disorders such as aggression, agitation, disturbance in attention, abnormal behaviour, psychomotor hyperactivity and learning disorder are principally observed in the paediatric population. Based on a limited number of post-marketing cases, Fanconi Syndrome, enuresis and gingival hyperplasia have been reported more frequently in paediatric patients than in adult patients.

Reporting of suspected adverse reactions

Reporting suspected adverse reactions after authorisation of the medicinal product is important. It allows continued monitoring of the benefit/risk balance of the medicinal product. Healthcare professionals are asked to report any suspected adverse reactions via Yellow Card Scheme at: www.mhra.gov.uk/yellowcard or search for MHRA Yellow Card in the Google Play or Apple App Store.

4.9. Overdose

Symptoms

Cases of accidental and deliberate valproate overdosage have been reported.

At plasma concentrations of up to 5-6 times the maximum therapeutic levels, there are unlikely to be any symptoms other than nausea, vomiting and dizziness.

Clinical signs of massive overdose, i.e. plasma concentration 10 to 20 times maximum therapeutic levels, usually include CNS depression or coma with muscular hypotonia, hyporeflexia, miosis, impaired respiratory function, metabolic acidosis, hypotension and circulatory collapse/shock. A favourable outcome is usual. However, some deaths have occurred following massive overdose.

Symptoms may however be variable and seizures have been reported in the presence of very high plasma levels (see also section 5.2). Cases of intracranial hypertension related to cerebral oedema have been reported.

The presence of sodium content in the valproate formulations may lead to hypernatraemia when taken in overdose.

Management

Hospital management of overdose should be symptomatic, including cardio-respiratory monitoring. Gastric lavage may be useful up to 10 to 12 hours following ingestion.

In case of valproate overdose resulting in hyperammonaemia, carnitine can be given through IV route to attempt to normalize ammonia levels.

Naloxone has been successfully used in a few isolated cases, sometimes in association with activated charcoal given orally.

In case of massive overdose, haemodialysis and haemoperfusion have been used successfully.