Most people know clarithromycin as a go-to antibiotic for respiratory infections — but it’s also used for skin infections and as part of H. pylori treatment for ulcers. It works by stopping bacteria from growing. That’s great when an infection is bacterial, harmful when it’s not. So first rule: only use clarithromycin when a clinician prescribes it.
If you’ve been prescribed clarithromycin, here are the basics you’ll want to know right away: typical adult doses are 250–500 mg twice daily for 7–14 days for common infections. There’s also a 500 mg extended‑release tablet that’s usually taken once daily. Children get a weight-based dose — your pediatrician will give the exact numbers. Never split doses or skip the full course; stopping early can cause resistance and treatment failure.
Most side effects are mild: nausea, diarrhea, stomach pain, and a strange metallic taste are common. More serious issues include liver problems, severe allergic reactions, and heart rhythm changes (QT prolongation). If you have existing heart rhythm issues, low potassium/magnesium, or severe liver disease, tell your doctor before taking clarithromycin.
Clarithromycin blocks the CYP3A4 enzyme. That matters because it raises levels of other drugs you might be taking. Don’t mix clarithromycin with simvastatin or lovastatin (risk of muscle damage), colchicine (risk of toxicity), certain antiarrhythmics, or some benzodiazepines without medical advice. If you’re on warfarin, antibiotics can affect INR — expect closer monitoring.
Use clarithromycin only when needed. Overuse contributes to resistant bacteria, which makes future infections harder to treat. Pregnant or breastfeeding? Clarithromycin is typically avoided unless the benefit clearly outweighs the risk; discuss alternatives with your provider.
Storing the medicine is simple: keep tablets at room temperature, away from moisture and direct light. Finish the prescribed course even if you feel better after a couple of days — that helps prevent relapse and resistance.
Want to buy clarithromycin online? Be careful. Only use pharmacies that require a prescription, show clear contact info, and have accreditation or recognizable third-party seals. Avoid sites selling antibiotics without a prescription or offering suspiciously low prices. If you need help, read our guide "How to Buy Clarithromycin Online Safely" on Hot-Med.com — it walks through red flags and safer options for buying meds online in different countries.
If symptoms get worse, if you develop a high fever, breathing problems, yellowing skin or eyes, or signs of a severe allergic reaction (rash, swelling, trouble breathing), stop the drug and seek medical care immediately. Questions about interactions, dosing for kids, or alternatives? Ask your clinician — they can match the right antibiotic to your diagnosis and medical history.
Tired of using Amoxil or looking for something that suits you better? Discover various antibiotic alternatives available in 2025, each with their own unique set of benefits and drawbacks, to help you find the right option for your medical needs.
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