Clarithromycin

In Aotearoa New Zealand clarithromycin is available as tablets, liquid and can be given as an injection in the hospital.

• The usual adult dose is 500 mg twice a day. The dose may be lower if you have kidney problems.
• The dose for children will depend on their body weight. It is usually given 2 times a day.
• Your doctor will advise you on how long to take clarithromycin for (usually 7–14 days).
• For most infections, you should feel better within a few days.
• Always take your clarithromycin 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. 

• Timing of your doses: Take your doses at the same times each day. Try to space your doses evenly throughout the day – this should be in the morning and in the evening. You can take clarithromycin with or without food. Swallow the tablets with a drink of water.
• Missed dose: If you forget to take your dose at the correct time, take it as soon as you remember. Try to take the correct number of doses each day. Do not take 2 doses at the same time to make up for a forgotten dose.
• Finish the course: Take the whole course of antibiotics for the number of days your doctor has told you to. Do not stop taking it, even if you feel your infection has cleared up. If you stop your treatment early, your infection could come back.

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

• Clarithromycin does not have direct interactions with alcohol. This means that most people could have the occasional drink while taking it without any serious problems. However, if clarithromycin makes you feel sick (nausea), do not drink alcohol as it will make you feel worse.
• If you are taking the contraceptive pill, you do not usually need to use additional contraception if you're taking clarithromycin. But if the antibiotic or the illness they're treating cause diarrhoea or vomiting, lasting more than 24 hours, absorption of the contraceptive pill may be affected. If this happens, ask your doctor or pharmacist for advice about contraception over the following few days.

Like all medicines, clarithromycin can cause side effects, although not everyone gets them. If you're concerned about any symptoms you think might be related to your medicine, talk to your healthcare provider. The following information offers some guidance but doesn't include all possible side effects.

Common side effects

Tell your healthcare provider if these side effects bother you.

• Nausea (feeling sick) or vomiting (being sick): Take clarithromycin with or after food. If you're sick (vomit) less than 30 minutes after having a dose of clarithromycin, take the same dose again. But, if you're sick (vomit) and it's more than 30 minutes after having a dose of clarithromycin, you don't need to take another dose. 
• Diarrhoea (runny poo): Drink plenty of fluids such as water to avoid dehydration.
• Headache.
• Changes in your taste, sore mouth or dry mouth.
• Small white patches in your mouth or a white furry tongue (oral thrush): Ask your healthcare provider for advice.
• Vaginal itching, soreness or discharge (vaginal thrush): Ask your healthcare provider for advice.

Tell your healthcare provider immediately or phone Healthline free on 0800 611 116 if these occur

• Hearing loss, ringing in the ears.
• Signs of problems with your liver such as yellowing of the skin or eyes, dark urine, stomach pain, pale stools.
   

Phone 111 for an ambulance or go to your nearest accident and emergency (A&E) clinic if these occur

• Signs of an allergic reaction such as itchy skin, and rash, swollen lips or tongue, problems breathing, like a tight chest or shortness of breath.

Read more about medicines and side effects and reporting a reaction you think might be a side effect.