Flucloxacillin
Also known as: Floxapen
What it's for
Flucloxacillin is an antibiotic for skin infections, wound infections, and bone infections. It works against bacteria that are resistant to other penicillins.
Comes as: Capsules or liquid
How to take it
- Adults: Usually 250mg to 500mg, 4 times a day.
- Take on an empty stomach - 1 hour before or 2 hours after food.
- Space doses evenly through the day.
- Complete the full course even if you feel better.
Doses here are typical. Always follow the instructions from your prescriber or on the packet — they come first.
Common side effects
- Feeling sick or diarrhoea
- Stomach pain
- Skin rash
The leaflet inside the packet lists all known side effects.
Important safety points
- Tell your doctor if you are allergic to penicillin
- Can rarely cause liver problems - tell your doctor if you get yellowing skin
- Take on an empty stomach for best absorption
Get medical help urgently if…
- You have yellowing of your skin or eyes
- You have severe stomach pain
- You have a severe skin rash or blistering
- You have swelling of your face, lips, or tongue
Call NHS 111 for urgent advice, or 999 if someone is seriously unwell.
Before you act on anything here
This page is general information, written to help you understand — it is not personal medical advice and it cannot tell you what is right for you. Talk to your own GP, pharmacist or nurse about your own health.
- Need help now but it's not an emergency? Call NHS 111 or use 111.nhs.uk.
- Emergency? Call 999 or go to A&E.