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Flucloxacillin 1g powder for solution for injection/infusion vials

⚠ This medicine appears to have been discontinued

The electronic medicines compendium (emc) no longer publishes a Summary of Product Characteristics for this product, which usually means it is no longer marketed in the UK. The patient leaflet below is kept for reference, but the product may not be available.

If you were prescribed this medicine, other products containing Flucloxacillin sodium may still be available. Do not stop your treatment — ask your pharmacist or GP what to use instead.

Active substance: Flucloxacillin sodium

Source: electronic medicines compendium (emc)
Official leaflet: Read the PIL on emc

What it is and what it is used for

FOR Your medicine contains the active substance flucloxacillin (as flucloxacillin sodium), which is one of a group of medicines called "penicillins". These medicines are also known as "antibiotics" and they work by killing the bacteria that cause infections. Flucloxacillin injection is used to treat a wide range of bacterial infections which may include those affecting:

  • The chest (pneumonia, emphysema and lung abscess)
  • Tonsils (tonsillitis, quinsy)
  • Pharynx (pharyngitis)
  • Sinuses (sinusitis)
  • Ears (otitis media and otitis externa)
  • Skin and soft tissue (boils, abscesses, carbuncles, impetigo, cellulites, furunculosis, ulcers and acne)
  • Wounds and burns
  • Heart (endocarditis)
  • Bones and joints (osteomyelitis)
  • Membranes of the brain (meningitis)
  • Gut (enteritis)
  • Blood (Septicaemia)
  • Kidney, bladder or the urethra (the tube which carries urine from the bladder). Flucloxacillin injection can also be used to prevent infections following skin grafts or during major surgical procedures, particularly in heart or orthopaedic surgery.

What you need to know before you take it

FLUCLOXACILLIN INJECTION You should not be given Flucloxacillin Injection if:

  • You are allergic to flucloxacillin, penicillin, cephalosporins or other antibiotics (see symptoms in section 4)

•

You have had jaundice (your skin and the whites of your eyes turn yellow) or you have had other liver problems when you have been given flucloxacillin previously. You must tell your doctor or nurse if any of these apply to you. Flucloxacillin should not be given into the eye or under the eye lids. Warnings and precautions Talk to your doctor or nurse before you are given Flucloxacillin injection if any of the following apply to you:

  • You have ever had a skin rash or swelling of the face or neck when taking an antibiotic
  • You have any serious illness other than this infection
  • You are being treated for liver or kidney problems or heart problems (as you may require a lower dose than normal)
  • You are on a low sodium diet (See "Flucloxacillin injection contains sodium")
  • You are being treated for an infection such as syphilis or leptospirosis
  • You are aged 50 or above
  • You have porphyria (your doctor will have told you)
  • You are a known carrier of the HLA-B* 5701 allele
  • You are taking or will be taking paracetamol. There is a risk of blood and fluid abnormality (high anion gap metabolic acidosis) which occurs when there is an increase in plasma acidity when flucloxacillin is used together with paracetamol, particularly in certain groups of patients at risk e.g. patients with severe kidney impairment, sepsis or malnutrition, especially if the maximum daily doses of paracetamol are used. High anion gap metabolic acidosis is a serious disease that must have urgent treatment. Special care is essential in the newborn because of the risk of jaundice and high blood levels of flucloxacillin. The use of flucloxacillin, especially in high doses, may reduce the potassium levels in the blood (hypokalaemia). Your doctor may measure your potassium levels regularly during therapy with higher doses of flucloxacillin. Tests Regular monitoring of liver and kidney function should be performed whilst taking flucloxacillin for a long period of time. Tell your doctor that you are taking Flucloxacillin if you are having urine tests or blood tests because it may affect the results. Other medicines and Flucloxacillin Tell your doctor or nurse if you are taking, have recently taken or might take any other medicines, especially:
  • Probenecid (used for the treatment of gout)
  • Methotrexate (used to treat some tumours)
  • Chloramphenicol or tetracycline (anti-bacterial medicines)
  • Voriconazole (used against fungal infections) If you are being treated with Flucloxacillin, this can affect some blood and urine test results. Pregnancy and breast-feeding Tell the doctor or nurse if you are pregnant, think you might be pregnant or if you are breast feeding before you are given this medicine. Driving and using machines This medicine has no known effects on the ability to drive or use machines. Flucloxacillin injection contains sodium

250mg vial: This medicine contains less than 1 mmol sodium (23 mg) per vial, that is to say essentially "sodium free". 500mg/1g vial: These medicines contain 26mg/52mg sodium (main component of cooking/table salt) in each 500mg and 1g vial respectively. This is equivalent to 1.3% and 2.6% of the recommended maximum daily dietary intake of sodium for an adult.

How to take it

Your doctor or nurse will prepare your injection in the form of a liquid. They will inject this into a muscle (intramuscular) or into a vein (intravenous). It can also be given to you by injection into a joint, or injection into the lining of the lung, or by breathing in the medicine from a mask (nebuliser). Your doctor will decide how much you need each day and how often the injections should be given. The usual doses are as follows. Adults and children over 12 years: The recommended total daily dosage of 1 g – 6 g administered in 3-6 divided doses, by intravenous (i.v.) or intramuscular (i.m). injection. No intramuscular single bolus injection should exceed 2 g. The maximum dose of 12 g per day should not be exceeded. In cases of severe infections: Up to 8 g per day administered in three to four infusions (over 20 to 30 min). Premature infants, neonates, sucklings and infants Other pharmaceutical forms/strengths may be more appropriate for administration to this population. For infections of the bones and joints (osteomyelitis) or the heart (endocarditis) – up to 8g daily can be given in divided doses, every 6 to 8 hours. Flucloxacillin may be administered by other routes, together with systemic therapy (proportionally lower doses should be given in children)

  • by injection into the lining of the lung: 250 mg once daily
  • by breathing in the medicine from a mask (nebuliser): 125 mg to 250 mg four times a day
  • by injection into a joint: – 250 mg to 500 mg once daily Use in children and adolescents Under 12 years of age The recommended dose is 25 to 50 mg/kg/24 hours administered in three to four equally divided doses by i.m. or i.v. injection. In cases of severe infections: Up to 100 mg/kg/24 hours in three to four divided doses. No single bolus injection or infusion should exceed 33 mg/kg. Aged 10 to 14 years The recommended dose is a daily dose of 1.5 g to 2 g. Aged 6 to 10 years: 0.75 g to 1.5 g, divided into three to four equal doses. Severe kidney disease Your doctor may reduce your dose, maximum dose in adults is 1g every 8 to 12 hours. These doses can be increased in more serious infections.

To prevent infections after an operation, the usual dose is 1 to 2g before the operation when you are given your anaesthetic. This is then followed by 500mg four times a day for up to three days after your operation. If you think you have missed an injection, or had too many injections, speak to your doctor or nurse. If you are given more of this medicine than you should This is unlikely to happen but if it does, the doctor will treat any symptoms that follow.

Possible side effects

Like all medicines, Flucloxacillin Injection can cause side effects, although not everybody gets them. STOP taking Flucloxacillin Injection and contact your doctor straight away if you experience any of the following side effects:

  • Severe diarrhoea with bleeding)
  • Your skin or the whites of your eyes turn yellow
  • Your urine becomes darker or your faeces become paler
  • Any unexplained bleeding or bruising or skin discolouration
  • Convulsions (fits) at high doses
  • Tiredness, breathlessness, light-headedness, a rapid weak pulse, palpitations or headaches, these may be signs of the destruction of red blood cells (causing anaemia)
  • Skin rash and itching
  • Blistering of the skin, mouth, eyes or genitals
  • Any sudden wheeziness, difficulty in breathing or dizziness
  • Any swelling of the face, neck or tongue
  • Serious skin reactions
  • A red, scaly rash with bumps under the skin and blisters (exanthematous pustulosis). Some of these reactions can be delayed for several weeks after finishing treatment. The following side effects may also occur. Tell your doctor if any of these become troublesome. Common side effects (may affect up to 1 in 10 people)
  • Minor gastrointestinal disturbances e.g. stomach upset or diarrhoea. Very rare side effects (may affect up to 1 in 10,000 people)
  • Reduction (reversible) in blood cell counts which makes infections more likely
  • Inflammation of the kidney, bowel and/or liver. Liver problems may be severe and very rarely deaths have been reported (mainly in people with pre-existing liver problems or over 50's)
  • Joint pain, muscle pain. This may develop after 2 days or more from the start of treatment
  • Fever. This may develop after 2 days or more from the start of treatment
  • Blood and fluid abnormality (high anion gap metabolic acidosis) which occurs when there is an increase in plasma acidity when flucloxacillin is used together with paracetamol, particularly in the presence of risk factors (see "Warnings and precautions" above). Not known (frequency cannot be estimated from the available data)
  • Low potassium levels in the blood (hypokalaemia), which can cause muscle weakness, twitching or abnormal heart rhythm. Reporting of side effects If you get any side effects, talk to your doctor, nurse, or pharmacist. This includes any possible side effects not listed in this leaflet. You can also report side effects directly 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.

By reporting side effects you can help provide more information on the safety of this medicine.

How to store it

FLUCLOXACILLIN INJECTION Keep this medicine out of the sight and reach of children. Do not use this medicine after the expiry date which is stated on the carton and vial after EXP. The expiry date refers to the last day of that month. Store vials below 25°C. Your doctor, pharmacist or nurse will know how to store Flucloxacillin Injection properly. Do not use this medicine if you notice signs of discoloration. Do not throw away any medicines via wastewater or household waste. Ask your pharmacist how to throw away medicines you no longer use. These measures will help protect the environment.

Contents of the pack and other information

What Flucloxacillin injection contains Each vial contains 250mg, 500mg or 1g of Flucloxacillin (as flucloxacillin sodium). There are no other ingredients. What Flucloxacillin injection looks like and contents of the pack: Flucloxacillin injection is a white powder in a glass vial. Each carton contains 1, 5, 10, 20 or 50 glass vials. Not all pack sizes may be marketed. Marketing Authorisation Holder: Ibigen S.r.l. Via Fossignano 2, 04011 Aprilia (LT) Italy Manufacturer: Istituto Biochimico Italiano S.p.A. Via Fossignano 2, 04011 Aprilia (LT) Italy This leaflet was last revised in 09/2023. INFORMATION FOR THE HEALTHCARE PROFESSIONAL The following information is intended for medical or healthcare professionals only. Incompatibilities

  • This medicine must not be mixed with other medicines except those mentioned below (Instructions for use and handling)
  • Flucloxacillin should not be mixed with blood products or other proteinaceous fluids (e.g. protein hydrolysates) or with intravenous lipid emulsions
  • If flucloxacillin is prescribed concurrently with an aminoglycoside, the two antibiotics should not be mixed in the syringe, intravenous fluid container or giving set as precipitation may occur. Shelf life 36 months unopened. After opening: 24 hours. Special precautions for storage Store below 25°C. Reconstituted solution: From a microbiological point of view, the product should be used immediately. If not used immediately, in-use storage times and conditions prior to use are the responsibility of the user and would normally not be longer than 24 hours at 2 to 8°C unless reconstitution/ dilution has taken place in controlled and validated aseptic conditions.

Administration Intramuscular: Add 1.5 ml Water for Injections to 250 mg vial contents. Add 2 ml Water for Injections to 500 mg vial contents. Intravenous: Dissolve 250-500 mg in 5-10 ml Water for Injections. Dissolve 1 g in 15-20 ml Water for Injections. Administer by slow intravenous injection (three to four minutes). Flucloxacillin may also be added to infusion fluids or injected, suitably diluted, into the drip tube over a period of three to four minutes. Intrapleural: Dissolve 250 mg in 5-10 ml Water for Injections. Intra-articular: Dissolve 250-500 mg in up to 5 ml Water for Injections or 0.5% lidocaine hydrochloride solution. Nebuliser solution: Dissolve 125-250 mg of the vial contents in 3 ml sterile water. The following displacement volumes have been determined: Strength Reconstitution volume 250 mg 1.5 – 10 ml 500 mg 2 – 10 ml 1g 15 – 20 ml

Displacement volume (approximate) 0.2 ml 0.35 ml 0.6 ml

Instructions for use and handling Contact with flucloxacillin should be avoided since skin sensitisation may occur. Flucloxacillin powder for solution may be added to the following intravenous fluids: Water for Injections, sodium chloride 0.9%, glucose 5%, sodium chloride 0.18% with glucose 4%, Compound Sodium Lactate Intravenous Infusion (Ringer-Lactate solution; Hartmann's Solution). N.B. FLUCLOXACILLIN VIALS ARE NOT SUITABLE FOR MULTIDOSE USE. Any unused medicinal product or waste material should be disposed of in accordance with local requirements. Posology and method of administration Depends on the age, weight and renal function of the patient, as well as the severity of the infection. Usual adult dosage (including elderly patients) Adults and adolescents over 12 years of age Total daily dosage of 1 g – 6 g administered in 3-6 divided doses, by i.v. or i.m. injection. In cases of severe infections: Up to 8 g per day administered in three to four infusions (over 20 to 30 min). No intramuscular single bolus injection should exceed 2 g. The maximum dose of 12 g per day should not be exceeded. Osteomyelitis, endocarditis – Up to 8 g daily, in divided doses six to eight hourly. Surgical prophylaxis – 1 to 2 g IV at induction of anaesthesia followed by 500 mg six hourly IV, IM or orally for up to 72 hours. Flucloxacillin may be administered by other routes in conjunction with systemic therapy. (Proportionately lower doses should be given in children.) Intrapleural – 250 mg once daily. By nebuliser – 125 to 250 mg four times a day. Intra-articular – 250 to 500 mg once daily. Paediatric population Premature infants, neonates, sucklings and infants Other pharmaceutical forms/strengths may be more appropriate for administration to this population.

Children under 12 years of age The recommended dose is 25 to 50 mg/kg/24 hours administered in three to four equally divided doses by i.m. or i.v. injection. In cases of severe infections: Up to 100 mg/kg/24 hours in three to four divided doses. No single bolus injection or infusion should exceed 33 mg/kg. Children aged 10 to 14 years usually receive a daily dose of 1.5 g to 2 g and children aged 6 to 10 years 0.75 g to 1.5 g, divided into three to four equal doses. Renal impairment: In common with other penicillins, flucloxacillin usage in patients with renal impairment does not usually require dosage reduction. However, in the presence of severe renal failure (creatinine clearance < 10 ml/min) a reduction in dose or an extension of dose interval should be considered. The maximum recommended dose in adults is 1 g every 8 to 12 hours. Flucloxacillin is not significantly removed by dialysis and hence no supplementary dosages need to be administered either during, or at the end of the dialysis period. Hepatic impairment No dose reduction is necessary in patients with reduced hepatic function.

Frequently asked questions about Flucloxacillin 1g powder for solution for injection/infusion vials

How do I take Flucloxacillin 1g powder for solution for injection/infusion vials?

Flucloxacillin 1g powder for solution for injection/infusion vials comes as injection containing 1g. Always follow the dose your doctor or pharmacist has given you, and read the leaflet that comes with the medicine.

What is the active substance in Flucloxacillin 1g powder for solution for injection/infusion vials?

The active substance in Flucloxacillin 1g powder for solution for injection/infusion vials is flucloxacillin sodium.

Are there equivalent medicines to Flucloxacillin 1g powder for solution for injection/infusion vials?

Medicines with the same active substance, strength and form include: Flucloxacillin 1g Powder for Solution for Injection, Flucloxacillin 1g Powder for Solution for Injection or Infusion. They are interchangeable only if your prescriber or pharmacist says so.

Where does this information come from?

This leaflet reproduces the patient information leaflet approved for Flucloxacillin 1g powder for solution for injection/infusion vials, as published on the electronic medicines compendium (emc). The version printed inside your medicine’s packaging is the one that applies to you.

Can I get Flucloxacillin 1g powder for solution for injection/infusion vials without a prescription?

Whether a medicine is available over the counter or on prescription only depends on its licence. Check the leaflet, or ask your pharmacist — they can tell you straight away.

About this leaflet

The text above reproduces the patient information leaflet approved for this medicine, restructured for easier reading.

Medical disclaimer: This page is for information only and does not replace advice from your doctor or pharmacist. Always read the leaflet supplied with your medicine. If you are unwell, call NHS 111; in an emergency, call 999.

Medicines with the same active substance: Flucloxacillin sodium (15 medicines)
See every medicine containing this substance, or browse the full A–Z of active substances.
⚕For healthcare professionals — Summary of Product Characteristics (SmPC)Full SmPC: dosage, interactions, contraindications, warnings+
Technical information intended for healthcare professionals (doctors and pharmacists). The Summary of Product Characteristics (SmPC) is the official document approved by the MHRA/EMA. It does not replace the patient leaflet or a doctor’s advice.

4.1. Therapeutic indications

Flucloxacillin is indicated for the treatment of infections due to sensitive Gram-positive organisms, including β-lactamase-producing staphylococci and streptococci. Typical indications include:

Skin and soft tissue infections:

Boils, Cellulitis, Infected burns

Abscesses, Infected skin conditions, Protection for skin grafts

Carbuncles e.g. ulcer, eczema, and acne.

Impetigo

Furunculosis, Infected wounds

Respiratory tract infections:

Pneumonia, Lung abscess, Emphysema

Sinusitis, Pharyngitis, Otitis media and externa

Tonsillitis, Quinsy

Other infections caused by flucloxacillin-sensitive organisms:

Osteomyelitis, Urinary tract infection

Enteritis, Meningitis

Endocarditis, Septicaemia

Flucloxacillin is also indicated for use as a prophylactic agent during major surgical procedures when appropriate; for example cardiothoracic and orthopaedic surgery.

Parenteral usage is indicated where oral dosage is inappropriate.

4.2. Posology and method of administration

Posology

Depends on the age, weight and renal function of the patient, as well as the severity of the infection.

Usual adult dosage (including elderly patients)

Adults and adolescents over 12 years of age

Total daily dosage of 1 g - 6 g administered in 3-6 divided doses, by i.v. or i.m. injection.

In cases of severe infections: Up to 8 g per day administered in three to four infusions (over 20 to 30 min).

No intramuscular single bolus injection should exceed 2 g.

The maximum dose of 12 g per day should not be exceeded.

Osteomyelitis, endocarditis - Up to 8 g daily, in divided doses six to eight hourly.

Surgical prophylaxis - 1 to 2 g IV at induction of anaesthesia followed by 500 mg six hourly IV, IM or orally for up to 72 hours.

Flucloxacillin may be administered by other routes in conjunction with systemic therapy. (Proportionately lower doses should be given in children.)

Intrapleural - 250 mg once daily.

By nebuliser - 125 to 250 mg four times a day.

Intra-articular - 250 to 500 mg once daily.

Paediatric population

Premature infants, neonates, sucklings and infants:

Other pharmaceutical forms/strengths may be more appropriate for administration to this population.

Children under 12 years of age

25 to 50 mg/kg/24 hours administered in three to four equally divided doses by i.m. or i.v. injection.

In cases of severe infections: Up to 100 mg/kg/24 hours in three to four divided doses.

No single bolus injection or infusion should exceed 33 mg/kg.

Children aged 10 to 14 years usually receive a daily dose of 1.5 g to 2 g and children aged 6 to 10 years 0.75 g to 1.5 g, divided into three to four equal doses.

Renal impairment:

In common with other penicillins, flucloxacillin usage in patients with renal impairment does not usually require dosage reduction. However, in the presence of severe renal failure (creatinine clearance < 10 ml/min) a reduction in dose or an extension of dose interval should be considered. The maximum recommended dose in adults is 1 g every 8 to 12 hours. Flucloxacillin is not significantly removed by dialysis and hence no supplementary dosages need to be administered either during, or at the end of the dialysis period.

Hepatic impairment

No dose reduction is necessary in patients with reduced hepatic function.

Method of administration

For instructions on preparation of the solutions for administration, see section 6.6.

4.3. Contraindications

Hypersensitivity to the active substance or other β-lactam antibiotics (e.g. penicillins, cephalosporins).

Flucloxacillin is contra-indicated in patients with a previous history of flucloxacillin-associated jaundice/hepatic dysfunction.

Ocular or subconjunctival administration is contraindicated.

4.4. Special warnings and precautions for use

Before initiating therapy with flucloxacillin, careful enquiry should be made concerning previous hypersensitivity reactions to β-lactams. Cross-sensitivity between penicillins and cephalosporins is well documented.

Serious and occasionally fatal hypersensitivity reactions (anaphylaxis) have been reported in patients receiving β-lactam antibiotics. Although anaphylaxis is more frequent following parenteral therapy, it has occurred in patients on oral therapy. These reactions are more likely to occur in individuals with a history of β-lactam hypersensitivity.

If anaphylaxis occurs, flucloxacillin should be discontinued and the appropriate therapy instituted. Serious anaphylactic reactions may require immediate emergency treatment with adrenaline (epinephrine). Ensure adequate airway and ventilation and give 100% oxygen. IV crystalloids, hydrocortisone, antihistamine and nebulised bronchodilators may also be required.

The occurrence at the treatment initiation of a feverish generalised erythema associated with pustula may be a symptom of acute generalised exanthematous pustulosis (AGEP) (see section 4.8). In case of AGEP diagnosis, flucloxacillin should be discontinued and any subsequent administration of flucloxacillin contra-indicated.

Hypokalaemia (potentially life threatening) can occur with the use of flucloxacillin, especially in high doses. Hypokalaemia caused by flucloxacillin can be resistant to potassium supplementation. Regular measurements of potassium levels are recommended during the therapy with higher doses of flucloxacillin. Attention for this risk is warranted also when combining flucloxacillin with hypokalaemia-inducing diuretics or when other risk factors for the development of hypokalaemia are present (e.g. malnutrition, renal tubule dysfunction).

Flucloxacillin should be used with caution in patients with evidence of hepatic dysfunction, patients ≥ 50 years and those with serious underlying disease. In these patients, hepatic events may be severe, and in very rare circumstances, deaths have been reported (see section 4.8).

Care is necessary if very high doses of flucloxacillin are given, especially if renal function is poor because of the risk of nephrotoxicity. Care is also necessary if large doses of sodium salts are given to patients with impaired renal function or heart failure.

Care is required when treating some patients with spirochaete infections such as syphilis or leptospirosis because the Jarisch- Herxheimer reaction may occur shortly after treatment with a penicillin is started.

Contact with flucloxacillin should be avoided since skin sensitisation may occur.

Caution is advised in patients with porphyria.

Special caution is essential in the newborn because of the risk of hyperbilirubinaemia. Studies have shown that, at high dose following parenteral administration, flucloxacillin can displace bilirubin from plasma protein binding sites, and may therefore predispose to kernicterus in a jaundiced baby. In addition, special caution is essential in the newborn because of the potential for high serum levels of flucloxacillin due to a reduced rate of renal excretion.

During prolonged treatments (e.g. osteomyelitis, endocarditis), regular monitoring of hepatic and renal functions is recommended.

Prolonged use may occasionally result in overgrowth of non-susceptible organisms.

In case of severe and persistent diarrhoea, the possibility of pseudomembranous colitis should be considered; flucloxacillin therapy should be discontinued.

There is evidence that the risk of flucloxacillin induced liver injury is increased in subjects carrying the HLA-B*5701 allele. Despite this strong association, only 1 in 500-1000 carriers will develop liver injury. Consequently, the positive predictive value of testing the HLA-B*5701 allele for liver injury is very low (0.12%) and routine screening for this allele is not recommended.

Caution is advised when flucloxacillin is administered concomitantly with paracetamol due to the increased risk of high anion gap metabolic acidosis (HAGMA). Patients at high risk for HAGMA are in particular those with severe renal impairment, sepsis or malnutrition especially if the maximum daily doses of paracetamol are used.

After co-administration of flucloxacillin and paracetamol, a close monitoring is recommended in order to detect the appearance of acid–base disorders, namely HAGMA, including the search of urinary 5-oxoproline.

If flucloxacillin is continued after cessation of paracetamol, it is advisable to ensure that there are no signals of HAGMA, as there is a possibility of flucloxacillin maintaining the clinical picture of HAGMA (see section 4.5).

This medicine contains approximately 52mg sodium per vial, equivalent to 2.6% of the WHO recommended maximum daily intake of 2g sodium for an adult. This should be included in the daily allowance of patients on sodium restricted diets.

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

Flucloxacillin (CYP450 inducer) has been reported to significantly decrease plasma voriconazole concentrations. If concomitant administration of flucloxacillin with voriconazole cannot be avoided, monitor for potential loss of voriconazole effectiveness (e.g. by therapeutic drug monitoring); increasing the dose of voriconazole may be needed.

Other antibacterials:

Since bacteriostatic drugs such as chloramphenicol and tetracycline may interfere with the bactericidal effect of penicillins in the treatment of meningitis or in other situations in which a rapid bactericidal effect is necessary, it is best to avoid concurrent therapy.

Immunosuppressants:

There is reduced excretion of methotrexate (increased risk of toxicity).

Uricosuric agents:

Plasma concentrations of flucloxacillin are enhanced if probenecid is given concurrently.

Interference with diagnostic tests:

Penicillins may produce false-positive results with the direct antiglobulin (Coombs') test, falsely high urinary glucose results with the copper sulphate test and falsely high urinary protein results, but glucose enzymatic tests (e.g. Clinistix) and bromophenol blue tests (e.g. Multistix or Albustix) are not affected.

Paracetamol

Caution should be taken when flucloxacillin is used concomitantly with paracetamol as concurrent intake has been associated with high anion gap metabolic acidosis, especially in patients with risk factors. (see section 4.4).

4.6. Fertility, pregnancy and lactation

Pregnancy

Data on a limited number of exposed pregnancies indicate no adverse effects of flucloxacillin on pregnancy or on the health of the foetus/new-born child. Animal studies do not indicate direct or indirect harmful effects with respect to pregnancy, embryonal/foetal development, parturition or postnatal development.

Caution should be exercised when prescribing to pregnant women.

Breastfeeding

Flucloxacillin diffuses into breast milk in a limited amount and in rare cases this can lead to diarrhoea and/or fungal colonisation of the mucosa in the infant. The possibility of sensitisation of the infant to beta-lactam drugs should be considered.

Fertility

There are no data available on fertility.

4.7. Effects on ability to drive and use machines

Flucloxacillin has no or negligible influence on the ability to drive and use machines.

4.8. Undesirable effects

Adverse reactions listed below are classified according to frequency and System Organ Class (SOC).

Very common (>1/10), common (>1/100, <1/10), uncommon (>1/1000, <1/100), rare (>1/10,000, <1/1000), very rare (<1/10,000), not known (cannot be estimated from the available data).

Unless otherwise stated, the frequency of the adverse events has been derived from more than 30 years of post-marketing reports.

MedDRA

System Organ Class

Frequency

Undesirable Effects

Blood and lymphatic system disorders

Very rare

Neutropenia (including agranulocytosis) and thrombocytopenia1. Eosinophilia. Haemolytic anaemia.

Immune system disorders

Very rare

Anaphylactic shock (see section 4.4), angioneurotic oedema. If any hypersensitivity reaction occurs, the treatment should be discontinued. (See also Skin and subcutaneous tissue disorders).

Nervous system disorders

Very rare

In patients suffering from renal failure, neurological disorders with convulsions are possible with the I.V. injection of high doses.

Gastrointestinal disorders

Common2

Minor gastrointestinal disturbances

Very rare

Pseudomembranous colitis3.

Metabolism and nutrition disorders

Very rare

Cases of high anion gap metabolic acidosis, when flucloxacillin is used concomitantly with paracetamol, generally in the presence of risk factors (see section 4.4).

Not known

Hypokalaemia

Hepato-biliary disorders

Very rare

Hepatitis and cholestatic jaundice (see section 4.4)4. Changes in liver function laboratory test results (reversible when treatment is discontinued). There is evidence that the risk of flucloxacillin induced liver injury is increased in subjects carrying the HLA-B*5701 allele5.

Skin and subcutaneous tissue disorders

Uncommon2

Rash, urticaria and purpura

Very rare

Erythema multiforme, Stevens-Johnson syndrome and toxic epidermal necrolysis (See also Immune system disorders)

Not known

AGEP - acute generalized exanthematous pustulosis (see section 4.4)

Musculoskeletal and connective tissue disorders

Very rare

Arthralgia and myalgia sometimes develop more than 48 hours after the start of the treatment

Renal and urinary disorders

Very rare

Interstitial nephritis1

General disorders and administration site conditions

Very rare

Fever sometimes develops more than 48 hours after the start of the treatment

1. These are reversible when treatment is discontinued.

2. The incidence of these AEs was derived from clinical studies involving a total of approximately 929 adult and paediatric patients taking flucloxacillin.

3. If pseudomembranous colitis develops, flucloxacillin treatment should be discontinued and appropriate therapy, e.g. oral vancomycin should be initiated.

4. Hepatitis and cholestatic jaundice may be delayed for up to two months post-treatment. In some cases the course has been protracted and lasted for several months. Hepatic events may be severe, and in very rare circumstances, deaths have been reported. Most reports of deaths have been in patients ≥ 50 years of age and in patients with serious underlying disease.

5. Despite this strong association, only 1 in 500-1000 carriers will develop liver injury. Consequently, the positive predictive value of testing the HLA-B*5701 allele for liver injury is very low (0.12%) and routine screening for this allele is not recommended.

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

Symptoms

Gastrointestinal effects such as nausea, vomiting and diarrhoea may be evident.

With high parenteral doses of penicillins, neurotoxicity (e.g. convulsions, encephalopathy), blood disorders (e.g. neutropenia, haemolytic anaemia, prolongation of bleeding time, defective platelet function) or electrolyte disturbances may occur.

Treatment

Treatment is symptomatic.

Flucloxacillin is not removed from the circulation by haemodialysis.

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