Clarithromycin: What It Is, How It Works, and What Alternatives Work Better

When you’re dealing with a stubborn sinus infection, strep throat, or a skin bug that won’t quit, your doctor might reach for clarithromycin, a macrolide antibiotic that stops bacteria from growing by blocking protein production. Also known as Biaxin, it’s one of the go-to choices for respiratory infections because it works well against common bugs like Streptococcus and H. pylori. Unlike penicillin, it’s often used when someone’s allergic to amoxicillin or when the infection doesn’t respond to simpler drugs.

Clarithromycin doesn’t work alone in the antibiotic world. It’s part of a family called macrolide antibiotics, a group of drugs that include erythromycin and azithromycin, all sharing a similar structure and mechanism. Ilosone and Zithromax are its close cousins—each with slight differences in how long they last in your body, how often you take them, and what side effects they cause. For example, azithromycin often needs just a 5-day course, while clarithromycin usually takes 7 to 14 days. But both can upset your stomach, and neither works against viruses like colds or the flu. If your infection is more serious or resistant, doctors might switch to amoxicillin, a penicillin-based antibiotic that’s cheaper and often just as effective for ear or sinus infections. Augmentin, which adds clavulanate to amoxicillin, is another common alternative when bacteria have started fighting back. The real choice isn’t just about which drug is strongest—it’s about your history, your allergies, your liver function, and whether you’ve taken antibiotics before.

People often ask if clarithromycin is better than other options. The answer? It depends. For H. pylori (the stomach bug linked to ulcers), clarithromycin is a key part of the combo therapy. For bronchitis or pneumonia, azithromycin might be preferred because you take fewer pills. And if you’ve had bad reactions to macrolides before, your doctor will likely pick something outside that family entirely—like doxycycline or cefdinir. What matters most isn’t the brand name, but whether the drug matches your specific bug, your body, and your lifestyle.

Below, you’ll find real comparisons between clarithromycin and other antibiotics—what works faster, what costs less, what causes fewer side effects, and when to avoid it altogether. No fluff. Just straight talk on what you need to know to understand your treatment and ask the right questions.