4.1. Therapeutic indications

Xenical is indicated in conjunction with a mildly hypocaloric diet for the treatment of obese patients with a body mass index (BMI) greater or equal to 30 kg/m2, or overweight patients (BMI ≥ 28 kg/m2) with associated risk factors.

Treatment with orlistat should be discontinued after 12 weeks if patients have been unable to lose at least 5 % of the body weight as measured at the start of therapy.

4.2. Posology and method of administration

Adults

The recommended dose of orlistat is one 120 mg capsule taken with water immediately before, during or up to one hour after each main meal. If a meal is missed or contains no fat, the dose of orlistat should be omitted.

The patient should be on a nutritionally balanced, mildly hypocaloric diet that contains approximately 30 % of calories from fat. It is recommended that the diet should be rich in fruit and vegetables. The daily intake of fat, carbohydrate and protein should be distributed over three main meals.

Doses of orlistat above 120 mg three times daily have not been shown to provide additional benefit.

The effect of orlistat results in an increase in faecal fat as early as 24 to 48 hours after dosing. Upon discontinuation of therapy, faecal fat content usually returns to pre-treatment levels, within 48 to 72 hours.

Special populations

The effect of orlistat in patients with hepatic and/or renal impairment, children and elderly patients has not been studied.

There is no relevant indication for use of Xenical in children.

4.3. Contraindications

- Hypersensitivity to the active substance or to any of the excipients.

- Chronic malabsorption syndrome.

- Cholestasis.

- Breast-feeding.

4.4. Special warnings and precautions for use

In clinical trials, the decrease in bodyweight with orlistat treatment was less in type II diabetic patients than in non-diabetic patients. Antidiabetic medicinal product treatment may have to be closely monitored when taking orlistat.

Co-administration of orlistat with ciclosporin is not recommended (see section 4.5).

Patients should be advised to adhere to the dietary recommendations they are given (see section 4.2).

The possibility of experiencing gastrointestinal adverse reactions (see section 4.8) may increase when orlistat is taken with a diet high in fat (e.g. in a 2000 kcal/day diet, > 30 % of calories from fat equates to > 67 g of fat). The daily intake of fat should be distributed over three main meals. If orlistat is taken with a meal very high in fat, the possibility of gastrointestinal adverse reactions may increase.

Cases of rectal bleeding have been reported with Xenical. Prescribers should investigate further in case of severe and/or persistent symptoms.

The use of an additional contraceptive method is recommended to prevent possible failure of oral contraception that could occur in case of severe diarrhoea (see section 4.5).

Coagulation parameters should be monitored in patients treated with concomitant oral anticoagulants (see section 4.5 and 4.8).

The use of orlistat may be associated with hyperoxaluria and oxalate nephropathy leading sometimes to renal failure. This risk is increased in patients with underlying chronic kidney disease and/or volume depletion (see section 4.8).

Rare occurrence of hypothyroidism and/or reduced control of hypothyroidism may occur. The mechanism, although not proven, may involve a decreased absorption of iodine salts and/or levothyroxine (see section 4.5).

Antiepileptics patient: Orlistat may unbalance anticonvulsant treatment by decreasing the absorption of antiepileptic drugs, leading to convulsions (see section 4.5).

Antiretrovirals for HIV: Orlistat may potentially reduce the absorption of antiretroviral medicines for HIV and could negatively affect the efficacy of antiretroviral medications for HIV (see section 4.5).

This medicine contains less than 1 mmol sodium (23 mg) per capsule, that is to say essentially 'sodium-free'.

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

Ciclosporin

A decrease in ciclosporin plasma levels has been observed in a drug-drug-interaction study and also reported in several cases, when orlistat was administered concomitantly. This can lead to a decrease of immunosuppressive efficacy. Therefore the combination is not recommended (see section 4.4). However, if such concomitant use is unavoidable, more frequent monitoring of ciclosporin blood levels should be performed both after addition of orlistat and upon discontinuation of orlistat in ciclosporin treated patients. Ciclosporin blood levels should be monitored until stabilised.

Acarbose

In the absence of pharmacokinetic interaction studies, the concomitant administration of orlistat with acarbose should be avoided.

Oral anticoagulants

When warfarin or other anticoagulants are given in combination with orlistat, international normalised ratio (INR) values should be monitored (see section 4.4).

Fat soluble vitamins

Treatment with orlistat may potentially impair the absorption of fat-soluble vitamins (A, D, E and K).

The vast majority of patients receiving up to four full years of treatment with orlistat in clinical studies had vitamin A, D, E and K and beta-carotene levels that stayed within normal range. In order to ensure adequate nutrition, patients on a weight control diet should be advised to have a diet rich in fruit and vegetables and use of a multivitamin supplement could be considered. If a multivitamin supplement is recommended, it should be taken at least two hours after the administration of orlistat or at bedtime.

Amiodarone

A slight decrease in plasma levels of amiodarone, when given as a single dose, has been observed in a limited number of healthy volunteers who received orlistat concomitantly. In patients receiving amiodarone treatment, the clinical relevance of this effect remains unknown but may become clinically relevant in some cases. In patients receiving concomitant amiodarone treatment, reinforcement of clinical and ECG monitoring is warranted.

Convulsions have been reported in patients treated concomitantly with orlistat and antiepileptic drugs e.g. valproate, lamotrigine, for which a causal relationship to an interaction cannot be excluded. Therefore, these patients should be monitored for possible changes in the frequency and/or severity of convulsions.

Rare occurrence of hypothyroidism and/or reduced control of hypothyroidism may occur. The mechanism, although not proven, may involve a decreased absorption of iodine salts and/or levothyroxine (see section 4.4).

There are some case reports of reduced efficacy of antiretroviral HIV medicines, antidepressants antipsychotics (including lithium) and benzodiazepines coincidental to the initiation of orlistat treatment in previously well-controlled patients. Therefore orlistat treatment should only be initiated after careful consideration of the possible impact in these patients.

Lack of interactions

No interactions with amitriptyline, atorvastatin, biguanides, digoxin, fibrates, fluoxetine, losartan, phenytoin, phentermine, pravastatin, nifedipine Gastrointestinal Therapeutic System (GITS), nifedipine slow release, sibutramine or alcohol have been observed. The absence of these interactions has been demonstrated in specific drug-drug-interaction studies.

The absence of an interaction between oral contraceptives and orlistat has been demonstrated in specific drug-drug interaction studies. However, orlistat may indirectly reduce the availability of oral contraceptives and lead to unexpected pregnancies in some individual cases. An additional contraceptive method is recommended in case of severe diarrhoea (see section 4.4).

4.6. Fertility, pregnancy and lactation

For orlistat no clinical data on exposed pregnancies are available.

Animal studies do not indicate direct or indirect harmful effects with respect to pregnancy, embryonal/foetal development, parturition or postnatal development (see section 5.3).

Caution should be exercised when prescribing to pregnant women.

As it is not known whether orlistat is secreted into human milk, orlistat is contra-indicated during breast-feeding.

4.7. Effects on ability to drive and use machines

Xenical has no influence on the ability to drive and use machines.

4.8. Undesirable effects

Adverse reactions to orlistat are largely gastrointestinal in nature. The incidence of adverse events decreased with prolonged use of orlistat.

Adverse events are listed below by system organ class and frequency. Frequencies are defined as: very common (≥1/10), common (≥1/100 to <1/10), uncommon (≥1/1,000 to <1/100), rare (≥1/10,000 to <1/1,000) and very rare (<1/10,000) including isolated reports.

Within each frequency grouping, undesirable effects are presented in order of decreasing seriousness.

The following table of undesirable effects (first year of treatment) is based on adverse events that occurred at a frequency of > 2 % and with an incidence ≥ 1 % above placebo in clinical trials of 1 and 2 years duration:

System organ class

Adverse reaction/event

Nervous system disorders

Very common:

Headache

Respiratory, thoracic and mediastinal disorders

Very common:

Common:

Upper respiratory infection

Lower respiratory infection

Gastrointestinal disorders

Very common:

Common:

Abdominal pain/discomfort

Oily spotting from the rectum

Flatus with discharge

Faecal urgency

Fatty/oily stool

Flatulence

Liquid stools

Oily evacuation

Increased defecation

Rectal pain/discomfort

Soft stools

Faecal incontinence

Abdominal distension*

Tooth disorder

Gingival disorder

Renal and urinary disorders

Common:

Urinary tract infection

Metabolism and nutrition disorders

Very common:

Hypoglycemia*

Infections and infestations

Very common:

Influenza

General disorders and administration site conditions

Common:

Fatigue

Reproductive system and breast disorders

Common:

Menstrual irregularity

Psychiatric disorders

Common:

Anxiety

* only unique treatment adverse events that occurred at a frequency of > 2 % and with an incidence ≥ 1 % above placebo in obese type 2 diabetic patients.

In a 4 year clinical trial, the general pattern of adverse event distribution was similar to that reported for the 1 and 2 year studies with the total incidence of gastrointestinal related adverse events occurring in year 1 decreasing year on year over the four year period.

The following table of undesirable effects is based on post-marketing spontaneous reports, and therefore the frequency remains unknown:

System organ class

Adverse reaction

Investigations

Increase in liver transaminases and in alkaline phosphatase.

Decreased prothrombin, increased INR and unbalanced anticoagulant treatment resulting in variations of haemostatic parameters have been reported in patients treated with anticoagulants in association with orlistat (see section 4.4 and 4.5)

Gastrointestinal disorders

Rectal bleeding

Diverticulitis

Pancreatitis

Skin and subcutaneous tissue disorders

Bullous eruptions

Immune system disorders

Hypersensitivity (e.g. pruritus, rash, urticaria, angioedema, bronchospasm and anaphylaxis)

Hepatobiliary disorders

Cholelithiasis

Hepatitis that may be serious. Some fatal cases or cases requiring liver transplantation have been reported.

Renal and urinary disorders

Oxalate nephropathy that may lead to renal failure

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 the 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

Single doses of 800 mg orlistat and multiple doses of up to 400 mg three times daily for 15 days have been studied in normal weight and obese subjects without significant adverse findings. In addition, doses of 240 mg tid have been administered to obese patients for 6 months. The majority of orlistat overdose cases received during post-marketing reported either no adverse events or adverse events that are similar to those reported with recommended dose.

Should a significant overdose of orlistat occur, it is recommended that the patient be observed for 24 hours. Based on human and animal studies, any systemic effects attributable to the lipase-inhibiting properties of orlistat should be rapidly reversible.