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Antibiotic (penicillin, anti-staphylococcal)

Flucloxacillin: uses, side effects & precautions

Also known as Floxapen, Flopen, Dicloxacillin (related drug).

Esta información es solo orientativa de carácter general y no constituye un consejo médico. Consulta siempre a un profesional sanitario cualificado para cualquier asunto médico personal. En caso de emergencia, llama al número de emergencias de tu zona.

What it is used for

  • Skin and soft-tissue infections such as cellulitis and infected wounds
  • Boils and abscesses
  • Some bone and joint infections
  • Certain infections caused by staph bacteria

How it works

Flucloxacillin is a penicillin antibiotic that is especially good against staph bacteria, which commonly cause skin infections. It stops bacteria from building their cell walls so they die. It is widely used outside North America; a close relative, dicloxacillin, is used in some regions.

How it is taken

Comes as capsules and a liquid (oral suspension), and an injection in hospital. Take it exactly as your doctor or pharmacist directs and follow the label. It is usually taken on an empty stomach for better absorption. Complete the full course as advised.

No doses here on purpose. The right strength and schedule depend on you — only a doctor or pharmacist should set them. Always follow your prescription and the label.

Common side effects

  • Nausea
  • Diarrhoea
  • Stomach upset
  • Mild rash
  • Thrush

Serious effects — get help

  • Yellowing of the skin or eyes or dark urine (possible liver problem, which can appear days or weeks after stopping)
  • Severe allergic reaction with swelling or breathing difficulty
  • Severe, persistent or bloody diarrhoea
  • Severe blistering skin reactions

If a reaction is severe — for example trouble breathing, swelling of the face or throat, or collapse — go to the nearest emergency room now or call your local emergency number. Do not wait for an online consultation.

Interactions to watch

  • Methotrexate
  • Blood thinners such as warfarin
  • Some other antibiotics
  • Certain gout medicines

Who should take care

  • Tell your clinician about any penicillin allergy
  • Tell your clinician if you have had liver problems with this medicine before
  • Tell your clinician if you have kidney problems
  • Take on an empty stomach when advised
  • Report yellowing of the skin or eyes, which can occur after the course ends

Frequently asked questions

What is flucloxacillin mainly used for?
It is especially used for skin and soft-tissue infections caused by staph bacteria, such as cellulitis, infected wounds and boils.
Should I take it on an empty stomach?
Yes, it is usually taken before food for better absorption. Follow your label and ask your pharmacist if unsure.
Can it affect my liver?
Rarely it can cause liver problems, sometimes appearing days or weeks after finishing. Seek medical advice if you notice yellowing of the skin or eyes or dark urine.
What if I am allergic to penicillin?
Do not take it and tell your clinician, who will choose an alternative antibiotic.
Is Flucloxacillin safe to take?
For most people it is safe when taken exactly as a doctor or pharmacist advises and as printed on the label. Tell your clinician about your other medicines and health conditions, and seek urgent care for any serious reaction.

Related conditions

Related medicines

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