Key takeaways
Cefaclor (generic name) and penicillin (generic name) are both antibiotics used to treat bacterial infections, but they belong to different classes. Cefaclor is a cephalosporin antibiotic, while penicillin is a penicillin antibiotic. Both work by preventing bacteria from making their protective covering, but cefaclor is generally used for a broader range of infections, such as bronchitis, strep throat, skin infections, and urinary tract infections. Penicillin, available as penicillin v potassium (Penicillin VK), is often used for strep throat, pneumonia, and staph skin infections. Cefaclor is usually taken 2 to 3 times a day, whereas penicillin is taken every 6 to 8 hours, which can be harder to remember. If you're allergic to penicillin, you might also be allergic to cefaclor, so it's important to let your provider know about any past reactions. Both antibiotics are available in generic forms, making them more affordable. However, many common bacteria are resistant to penicillin, limiting its effectiveness to specific infections.
