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Flucloxacillin

Sounds like 'flu-CLOX-i-SIL-in'

Key points about flucloxacillin

Flucloxacillin is an antibiotic used to treat infections caused by bacteria.
It is a penicillin antibiotic.
Find out how to take it safely and possible side effects.

mother and young son receiving medicine from the pharmacy

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Flucloxacillin is an antibiotic used to treat infections caused by bacteria, for example skin infections such as cellulitis. Flucloxacillin works by killing or stopping the growth of bacteria (bugs).

Flucloxacillin belongs to a group of antibiotics called penicillins. Like all antibiotics, flucloxacillin is not effective against infections caused by viruses.

For information on how to give flucloxacillin to children, see flucloxacillin information for parents and carers.(external link)

Allergy to penicillin

Before taking flucloxacillin: Tell your healthcare provider if you have had an allergic reaction to a medicine, especially a penicillin antibiotic. True penicillin allergy is rare – fewer than 5 out of 10,000 people are allergic to penicillin. Most people who think they have a penicillin allergy do not – read more about penicillins and penicillin allergy).
After taking flucloxacillin: If you develop signs of an allergic reaction such as skin rash, itching, swelling of your lips, face and mouth, or difficulty breathing, stop taking flucloxacillin and seek immediate medical attention.

In Aotearoa New Zealand flucloxacillin is available as capsules (250 mg and 500 mg) and liquid, and can be given as an injection in the hospital.

The dose of flucloxacillin will be different for different people depending on the type of infection.
The usual dose of flucloxacillin capsules for adults is 500 mg, 4 times a day. Some people may need a higher dose.
Your doctor will advise you on how long to take flucloxacillin for (usually 5 to 7 days).
Always take your flucloxacillin exactly as your doctor has told you. The pharmacy label on your medicine will tell you how much to take, how often to take it, and any special instructions.

Swallow the capsule with a glass of water: Don't chew them. You can take flucloxacillin with or without food. If you have nausea (feeling sick), try taking it with food.
Timing: Take flucloxacillin at the same times each day. Try to space your doses evenly throughout the day. For example, for 4 times a day dosing take it first thing in the morning, at around midday, late in the afternoon and at bedtime.
Missed dose: If you forget to take your dose, take it as soon as you remember. But if it is nearly time for your next dose, take the next dose at the right time. Don't take extra doses to make up for a forgotten dose. If you're not sure what to do, ask your healthcare provider.
Alcohol: You can drink alcohol while taking flucloxacillin but it can increase your risk of side effects such as nausea and vomiting. Avoid heavy drinking or binge drinking.
Complete the course: Take the whole course of antibiotics for the number of days your doctor has told you to. Don't stop taking it, even if you feel your infection has cleared up. If you stop your treatment early, your infection could come back. If you still feel unwell after finishing the course, go back to see your doctor.

Like all medicines, flucloxacillin can cause side effects, although not everyone gets them. Often side effects improve as your body gets used to the new medicine.

Side effects	What should I do?
Nausea (feeling sick) Stomach upset	It's quite common to feel sick (nausea) when you take flucloxacillin. Try taking each dose with food to help reduce the nausea. If you are sick (vomit) less than 30 minutes after having a dose of flucloxacillin, take the same dose again. But if you vomit more than 30 minutes after having a dose of flucloxacillin, you don't need to take another dose. Wait until the next normal dose.
Diarrhoea (runny poo)	This should settle after a few days. Drink plenty of fluids such as water or diluted juice to avoid dehydration. Tell your doctor if it bothers you.
Vaginal itching, soreness or discharge (thrush)	Tell your doctor or pharmacist.
Signs of an allergic reaction such as skin rash, itching, swelling of the lips, face, and mouth or difficulty breathing	Stop taking flucloxacillin. Tell your doctor immediately or ring Healthline 0800 611 116.
Signs of problems with your liver such as yellowing of the skin or eyes, dark urine, pain in the abdomen.	Tell your doctor immediately or ring Healthline 0800 611 116. These can occur up to 2 months after you've have stopped taking flucloxacillin and are more common with courses longer than 2 weeks and with older people.