clarithromycin at a glance
Medicine class
Macrolide antibiotic
Available forms
Immediate-release and prolonged-release tablets, oral suspension and hospital-administered intravenous infusion
Food
Immediate-release tablets and suspension may be taken with or without food; prolonged-release tablets must be taken with food
Interaction check
Ask a pharmacist or prescriber to review all medicines before treatment because clinically significant interactions can occur
What is clarithromycin used for?
Licensed uses vary by formulation and age group and apply to infections caused by susceptible organisms.
Upper and lower respiratory-tract infections, including bacterial pharyngitis, sinusitis, exacerbations of chronic bronchitis and community-acquired pneumonia.
Mild-to-moderate skin and soft-tissue infections, including folliculitis, cellulitis and erysipelas.
Acute otitis media in children, represented by oral-suspension products.
Eradication of Helicobacter pylori associated with peptic ulcer disease, using immediate-release tablets as part of combination treatment.
Hospital intravenous treatment when oral treatment is unsuitable.
How does clarithromycin work?
Clarithromycin binds to the bacterial 50S ribosomal subunit and inhibits protein synthesis, preventing susceptible bacteria from growing. Its 14-hydroxy metabolite also has antibacterial activity.
clarithromycin preparations and strengths
Solution for infusion
Route: Intravenous
Strengths: 500 mg
Modified-release tablet
Route: Oral
Strengths: 500 mg
Oral suspension
Route: Oral
Strengths: 125 mg/5 mL, 250 mg/5 mL
How to take clarithromycin
Follow the dispensing label and instructions from your healthcare professional.
Swallow tablets with water. Do not crush or chew prolonged-release tablets; take them with food.
Shake oral suspension well and measure it with the supplied oral syringe or medicine spoon, not a kitchen teaspoon.
Water or juice after the suspension may help with its bitter aftertaste.
Intravenous clarithromycin must be prepared and administered by healthcare professionals. It must not be injected rapidly or into a muscle.
clarithromycin side effects
Common or expected effects
- Nausea or vomiting
- Diarrhoea, abdominal pain or indigestion
- Altered or bitter taste
- Headache
- Difficulty sleeping
Get urgent medical advice
- Sudden swelling, breathing difficulty or collapse
- A blistering, peeling or widespread severe rash
- Fast or irregular heartbeat, faintness or collapse
- Yellow skin or eyes, dark urine or pale stools
- Severe or bloody diarrhoea, including after treatment
- Severe abdominal pain that may spread to the back
clarithromycin in pregnancy
Clarithromycin can be used during pregnancy when a doctor considers it appropriate. Available evidence does not show impaired fetal development, although reported associations with miscarriage may partly reflect the infection. Benefits and risks should be assessed carefully, particularly early in pregnancy.
clarithromycin while breastfeeding
Clarithromycin can generally be used cautiously while breastfeeding a full-term, healthy infant. Only very small amounts enter milk. Monitor for diarrhoea, vomiting, oral thrush, rash, irritability or poor feeding. Seek specialist advice for a premature or unwell infant or when using several medicines.
clarithromycin interactions
Clarithromycin inhibits important drug-metabolising enzymes and transporters and can contribute to QT prolongation. This list is not exhaustive.
Simvastatin or lovastatin
Concurrent use is contraindicated because increased statin exposure can cause myopathy or rhabdomyolysis.
Atorvastatin
Exposure and muscle-toxicity risk may increase; an alternative antibiotic or temporary statin management may be required.
Colchicine
Exposure and potentially fatal toxicity can increase; concurrent use is contraindicated by the selected product information.
Common questions about clarithromycin
Answers are fully visible for fast scanning and source review.
Does clarithromycin contain penicillin?
No. It is a macrolide antibiotic and is sometimes selected when a penicillin antibiotic is unsuitable, depending on the infection and allergy history.
Can clarithromycin be taken with food?
Immediate-release tablets and oral suspension can be taken with or without food. Prolonged-release tablets must be taken with food.
Sources
These sources were used to prepare and review this medicine page.
Prepared and reviewed by the iatroX editorial team.