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Terms Of Use


Brand Name(s) : Floxapen, Fluclomix, Ladropen
Side Effects


Flucloxacillin should be used with caution in:

  • liver disease
  • kidney problems
  • patients on sodium restricted diets
  • patients aged 50 years or older
  • patients with serious underlying diseases.

It should not be used in:

  • hypersensitivity (allergy) to penicillins

Also see list of precautions and interactions


Flucloxacillin capsules should be stored in the original packaging or in recloseable containers in a dry place. Flucloxacillin syrup should not be stored above 25°C. Once reconstituted, the syrup should be stored refrigerated (between 2 and 8°C) and used within 7 days. Flucloxacillin powder for injection should not be stored above 25°C. Once prepared for injection, it should be used immediately.


What is it used for?

  • Flucloxacillin is used to treat certain types of bacterial infection and to prevent bacterial infections occurring during major surgery.
  • It is an antibiotic, sometimes known as a penicillin.
  • It is used to treat particular types of infection caused by Gram-positive bacteria and is effective against bacteria (such as staphylococcal and streptococcal infections) that produce a substance (known as beta-lactamase or penicillinase) that can destroy many penicillins.
  • In general this drug is used treat infections of the ear, nose, and throat, blood, bones and joints, chest, gut, heart, kidney and skin, and to treat meningitis and urinary infections caused by Gram-positive bacteria. It is also used as a preventive therapy, to prevent such infections occurring during major surgery, in particular during heart or orthopaedic surgery.
  • Benefits of being on this drug can include controlling and stopping infections caused by Gram-positive bacteria. It can also prevent infections occurring during surgery improving recovery after your operation.

Listed below are the typical uses of flucloxacillin.

  • Skin and soft tissue infections, including burns, wound infections, protection for skin grafts, impetigo
  • Respiratory infections, including pneumonia, sinusitis, and tonsillitis
  • Other infections such as osteomyelitis (bone infection), urinary tract infection, gastroenteritis, meningitis, endocarditis (heart infection), septicaemia (blood infection)
  • As a prophylactic (preventive) agent during major surgical procedures, for example during heart and orthopaedic surgery

On occasion your doctor may prescribe this medicine to treat a condition not on the above list.


How often do I take it?

  • Take this medication orally usually four times a day, half to one hour before meals. For other forms of administration, for example, IV and IM, the medication will be prepared and administered by your doctor or other health care professional.
  • Use this medication for duration of prescription in order to get the most benefit from it.
  • Remember to use it at the same time each day - unless specifically told otherwise by your doctor.
  • It may take the whole duration of the prescription before the full benefit of this drug takes effect. Do not stop treatment early because some bacteria may survive and cause the infection to come back.
  • Certain medical conditions may require different dosage instructions as directed by your doctor.

What dose?

  • Dosage is based on your age, gender, medical condition, response to therapy, and use of certain interacting medicines.

Do I need to avoid anything?

  • Flucloxacillin is not known to interfere with your ability to drive or operate machinery. Consult your doctor or pharmacist for more details.

When can I stop?

  • Always complete the full course as prescribed by your doctor.


  • Minor gastrointestinal disturbances (diarrhoea)
  • Skin rash
  • Urticaria
  • Liver problems
  • Joint pain
  • Muscle pain
  • Fever

If any of these persist or you consider them severe then inform your doctor or pharmacist.

Tell your doctor immediately if you develop any of the following symptoms:

  • Allergic (hypersensitivity) reactions (very rarely, serious and occasionally fatal hypersensitivity reactions known as anaphylaxis may occur)

Remember that your doctor has prescribed this medication because he or she has judged that the benefit to you is greater than the risk of side effects. Many people using this medication do not have serious side effects.

A serious allergic reaction to this drug is unlikely, but seek immediate medical attention if it occurs. Symptoms of a serious allergic reaction include: rash, itching/swelling (especially of the face/tongue/throat), dizziness, trouble breathing.

This is not a complete list of possible side effects. If you notice other effects not listed above, contact your doctor or pharmacist.

The Yellow Card Scheme allows you to report suspected side effects from any type of medicine (which includes vaccines, herbals and over the counter medicines) that you are taking. It is run by the medicines safety watchdog called the Medicines and Healthcare products Regulatory agency (MHRA). Please report any suspected side effect on the Yellow Card Scheme website.


Before taking flucloxacillin, tell your doctor or pharmacist if you are allergic to it; or to other penicillins; or if you have any other allergies.

This medication should not be used if you have certain medical conditions. Before using this medicine, consult your doctor or pharmacist if you have: known hypersensitivity to penicillins.

Before using this medication, tell your doctor or pharmacist your medical history, especially any of the following: liver disease, any serious underlying illness.

Before having surgery, tell your doctor or dentist that you are taking this medication.

Does alcohol intake affect this drug?

  • Alcohol intake is not known to affect flucloxacillin.

The elderly: flucloxacillin should be used with caution in older patients (aged more than 50 years) as it may affect the liver.

Pregnancy and breastfeeding - please ensure you read the detailed information below


Flucloxacillin is suitable to take during pregnancy. Ask your doctor or pharmacist if you have any doubts or questions about this.

It is sensible to limit use of medication during pregnancy whenever possible. However, your doctor may decide that the benefits outweigh the risks in individual circumstances and after a careful assessment of your specific health situation.

If you have any doubts or concerns you are advised to discuss the medicine with your doctor or pharmacist.


Flucloxacillin is suitable to take if you are breastfeeding. However, trace amounts pass into the milk and the chance of hypersensitivity reactions occurring must be considered in breast-fed infants.

It is sensible to limit use of medication during breastfeeding whenever possible. However, your doctor may decide that the benefits outweigh the risks in individual circumstances and after a careful assessment of your specific health situation.

If you have any doubts or concerns you are advised to discuss the medicine with your doctor or pharmacist.


Your doctor or pharmacist may already be aware of any possible drug interactions and may be monitoring you for them. Do not start, stop, or change the dosage of any medicine before checking with them first.

There are medicines that are known to interact with flucloxacillin and your doctor may well have considered this, however if you are taking any of the following medicines please make sure your doctor or pharmacist is aware of this. Do not start, stop or change the dosage of any medicine before checking with them first.

This drug should not be used with the following medications because very serious, possibly fatal interactions may occur:

  • Probenecid
  • Blood-thinning drugs (e.g. warfarin)
  • Methotrexate
  • Sulfinpyrazone
  • Oral typhoid vaccine

If you are currently such medications, tell your doctor or pharmacist before starting flucloxacillin.

Before using this medication, tell your doctor or pharmacist of all prescription and non-prescription/herbal products you may use, especially of:

  • oral contraceptives

This information does not contain all possible interactions. Therefore, before using flucloxacillin, tell your doctor or pharmacist of all the products you use.


If you (or someone else) swallow a lot of capsules at the same time, or you think a child may have swallowed any, contact your nearest hospital casualty department or tell your doctor immediately. Symptoms of an overdose include feeling or being sick and diarrhoea.

If you think you, or someone you care for, might have accidentally taken more than the recommended dose of flucloxacillin or intentional overdose is suspected, contact your local hospital, GP or if in England call 111. In Scotland call NHS 24. In Wales, call NHS Direct Wales. In the case of medical emergencies, always dial 999.


If you miss a dose, take it as soon as you remember and carry on as before. Try to wait about four hours before taking the next dose. Do not double the dose to catch up.

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Source: Selected from data included with permission and copyrighted by Boots UK Limited. This copyrighted material is sourced from a licensed data provider and is not for distribution, except as may be authorised by the applicable terms of use.
CONDITIONS OF USE: The information in this database is intended to supplement, not substitute for, the expertise and judgement of healthcare professionals. The information is not intended to cover all possible uses, directions, precautions, drug interactions or adverse events, nor should it be construed to indicate that use of a particular medicine is safe, appropriate or effective for you or anyone else. A healthcare professional should be consulted before taking any medicine, changing any diet, or discontinuing any course of treatment.

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