Cefaclor: What It Is, How It Works, and What Alternatives You Should Know

When you’re dealing with a stubborn ear infection, sinusitis, or a skin bug that won’t quit, your doctor might reach for Cefaclor, a second-generation cephalosporin antibiotic used to treat common bacterial infections. Also known as CEFACLOR, it’s one of those medications that’s been around long enough to be trusted but isn’t as loud as some newer drugs. It works by breaking down the cell walls of bacteria, making it hard for them to survive and multiply. Unlike penicillin, which can trigger allergies in some people, Cefaclor is often a go-to alternative — especially if you’ve had a reaction to amoxicillin or other penicillin-based drugs.

But Cefaclor isn’t the only player in town. It’s part of a bigger family called cephalosporins, a class of antibiotics that includes drugs like cephalexin, cefdinir, and cefuroxime. These drugs are grouped by generations, and Cefaclor sits in the second wave — meaning it’s stronger against a wider range of bacteria than first-gen options like cephalexin, but not as broad-spectrum as third-gen drugs like ceftriaxone. You’ll also see it compared to amoxicillin, a penicillin-based antibiotic often used for similar infections, especially in kids. The big difference? Cefaclor holds up better against certain resistant strains, and it’s sometimes preferred when amoxicillin fails.

People often wonder if Cefaclor is worth the prescription when there are cheaper or newer options. The answer depends on your infection, your history, and your body’s reaction. For example, if you’ve had repeated ear infections that didn’t clear with amoxicillin, Cefaclor might be the next logical step. But if you’re dealing with something like pneumonia or a severe urinary tract infection, your doctor might skip straight to something stronger. And if you’ve had an allergic reaction to any beta-lactam antibiotic — penicillin, cephalosporin, or carbapenem — Cefaclor isn’t safe for you.

Side effects? They’re usually mild — stomach upset, diarrhea, or a rash. But in rare cases, it can trigger a serious allergic reaction or cause Clostridioides difficile infection, which leads to severe diarrhea. That’s why it’s never a drug to take without a confirmed bacterial diagnosis. Viral colds? No. Flu? No. Cefaclor doesn’t work on viruses, and using it when it’s not needed only makes resistance worse.

What you’ll find in the posts below is a clear look at how Cefaclor stacks up against other antibiotics — from common ones like amoxicillin and azithromycin to less familiar options like roxithromycin and furazolidone. You’ll see real comparisons on dosing, side effects, cost, and when each drug actually makes sense. No fluff. No marketing. Just straight talk on what works, what doesn’t, and what to ask your doctor if you’re unsure.