Keflex (cephalexin) — What it treats, how to take it, and how to stay safe

Keflex is the brand name for cephalexin, a common oral antibiotic many doctors prescribe for skin infections, ear infections, strep throat and some urinary tract infections. It works by stopping bacteria from building a protective cell wall so they can’t survive. That makes it a go-to for simple, short-course bacterial problems.

How Keflex is used

Doctors pick Keflex when the likely germs are susceptible to cephalosporins. Typical uses include: - Skin and soft tissue infections (like infected cuts or cellulitis). - Otitis media (middle ear infections), especially in children. - Sore throat caused by strep when a penicillin alternative is needed. - Uncomplicated urinary tract infections in some cases.

If you’re wondering whether your cough, sore throat or UTI needs Keflex, check with a clinician — antibiotics only help bacterial infections, not viruses.

Dosing, side effects and safety tips

Common adult doses range from 250 mg every 6–8 hours to 500 mg every 12 hours depending on the infection. For more severe infections a doctor might use higher or more frequent doses. Kids get weight-based dosing — that’s why a pediatrician’s guidance matters. Always finish the full course unless told otherwise.

Side effects are usually mild: stomach upset, nausea, diarrhea, and sometimes a rash. If you get severe diarrhea, a high fever, bloody stools, or signs of an allergic reaction (hives, swelling, trouble breathing), stop the drug and seek care right away. People with severe penicillin allergy should mention it — there’s some chance of cross-reactivity, so your provider may choose a different antibiotic.

Kidney disease matters. Cephalexin is cleared by the kidneys, so doses often need to be adjusted if kidney function is reduced. Tell your doctor about other meds you take — probenecid can raise cephalexin levels, for example. Pregnant or breastfeeding? Cephalosporins are commonly used in pregnancy and are generally considered safe, but check with your clinician for your situation.

Not feeling better after 48–72 hours? Or do symptoms get worse? Call your provider. Also see the doctor immediately for high fever, spreading redness, or any breathing trouble.

Thinking of buying Keflex online? You should have a valid prescription. Use pharmacies with clear contact details, pharmacist access, and accreditation. Choosing generic cephalexin usually cuts cost without changing how well it works. Be cautious of sites selling antibiotics without a prescription or at suspiciously low prices — counterfeit meds are a real risk.

Got questions about dosage, interactions or where to buy safely? Ask your pharmacist or prescriber — they can match the right dose to your health, answer safety questions, and point you to reputable suppliers.