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Co-trimoxazole

Sounds like 'co-tri-mox-a-zole'

Key points about co-trimoxazole

Co-trimoxazole is an antibiotic used to treat different infections caused by bacteria.
Co-trimoxazole is also called Trisul® or Deprim®.
Find out how to take it safely and possible side effects.

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Co-trimoxazole is an antibiotic used to treat infections caused by bacteria, such as infections of the urinary tract, skin or chest.

Co-trimoxazole is made up of two antibiotics (trimethoprim and sulfamethoxazole). Sulfamethoxazole belongs to a group of antibiotics called sulphonamides.

It works by killing or stopping the growth of bacteria (bugs) which gets rid of the infection. It's not effective against infections caused by viruses.

In Aotearoa New Zealand co-trimoxazole is available as tablets and liquid and can also be given as an injection in the hospital.

The dose of co-trimoxazole will be different for different people depending on the type of infection and your age.
The usual dose for adults is 2 tablets twice a day.
The dose for children will depend on their body weight. It is usually given 2 times a day.
Your healthcare provider will advise you how long to take co-trimoxazole for (usually 5 to 7 days) but for urinary tract infections, it may only be needed for 3 days.
Always take your co-trimoxazole exactly as your healthcare provider 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.

Read more about the co-trimoxazole paediatric dose calculator.

Timing: Co-trimoxazole is usually taken 2 times a day. Try to space the doses evenly throughout the day such as the first thing in the morning and at bedtime. Ideally these times should be at 12 hours apart.
Capsules: Swallow the capsules with a drink of water. Don't chew them.
Liquid co-trimoxazole: Shake the bottle well and use an oral syringe or measuring spoon to measure each dose.
Food: You can take co-trimoxazole with or without food. If you get a sore tummy, take it with food.
Missed dose: If you forget to take your dose, take it as soon as you remember. But, if it's nearly time for your next dose, take the next dose at the usual time. Don’t take 2 doses at the same time to make up for a forgotten dose.
Finish the course: It’s best to take the whole course of antibiotics for the number of days your healthcare provider has told you to. You should start to get better after taking co-trimoxazole for a few days. If you don’t feel better or get more unwell, contact your healthcare provider. Don't stop taking it, even if you feel your infection has cleared up.

Here are some things to know when you're taking co-trimoxazole. Other things may be important as well, so ask your healthcare provider what you should know about.

Alcohol: Co-trimoxazole doesn't directly interact with alcohol. This means that most people could have the occasional drink while taking it without any serious problems. However, if co-trimoxazole makes you feel sick (nausea), don't drink alcohol as it will make you feel worse.
Driving: Co-trimoxazole can make you feel dizzy. Be careful when driving or using tools until you know how this medicine affects you.
Other medicines:
- Co-trimoxazole interacts with some medicines, (eg, methotrexate, warfarin, and sulfonylurea medicines for diabetes) herbal supplements and rongoā Māori, so check with your healthcare provider before starting co-trimoxazole and before starting any new products.
- If you're taking the contraceptive pill, you don't need to use additional contraception if you're taking co-trimoxazole. But if you have diarrhoea (runny poo) or vomiting (being sick) that lasts more than 24 hours, absorption of the contraceptive pill may be affected. If you have diarrhoea or vomiting, ask your healthcare provider for advice.
Pregnancy or breastfeeding: Talk to your healthcare provider if you're pregnant, planning a pregnancy or want to breastfeed.
Vaccines: Co-trimoxazole may stop the oral typhoid vaccine from working. Have a space of 3 days between the typhoid vaccine and this antibiotic.

Like all medicines, co-trimoxazole 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) Vomiting (being sick)	These are common. Try taking co-trimoxazole with food.
Diarrhoea (runny poos)	This is less common and should settle after a few days. Drink more fluids and eat simple foods such as toast and pasta. Tell your doctor if your diarrhoea is severe, contains blood or lasts more than a few days. If you have a lot of diarrhoea and you're taking the oral contraceptive pill, let your healthcare provider know.
Small white patches in your mouth or a white furry tongue (oral thrush) Vaginal itching, soreness or discharge (vaginal thrush)	These are common. Ask your healthcare provider for advice.
Skin rash, skin peeling or blisters on the body or inside the mouth, throat or nose	This is rare and more likely in the first week of treatment. Stop taking co-trimoxazole. Tell your doctor immediately or ring Healthline 0800 611 116.
Signs of problems with your liver such as yellow skin and eyes, dark urine and stomach pain	Tell your doctor immediately or ring Healthline 0800 611 116.
Allergic reaction such as skin rash, itching, swelling of the lips, face, and mouth or difficulty breathing	This is rare. Stop taking co-trimoxazole. Tell your doctor immediately or ring Healthline 0800 611 116.