Compare amoxicillin vs. Keflex

Head-to-head comparisons of medication uses, side effects, ratings, and more.

Amoxil (amoxicillin)

Prescription only

Keflex (cephalexin)

Prescription only
Treats bacterial infections.

Amoxil (amoxicillin) is a good and cheap antibiotic that comes in different forms to treat many types of bacterial infections.

3.7/ 5 average rating with 786 reviewsforamoxicillin
Treats bacterial infections.

Keflex (cephalexin) is good for treating many bacterial infections, and is available as a generic.

3.7/ 5 average rating with 686 reviewsforKeflex
Upsides
  • First choice medicine to treat many bacterial infections.
  • Available in generic.
  • Available in different forms: tablet, capsule, and liquid. The liquid comes in many different flavors to make it taste better for people who don't like pills.
  • Side effects are generally not too bad compared to other antibiotics.
  • Available in generic.
  • Available in different forms: tablet, capsule, and suspension.
  • Used to treat many types of bacterial infections.
  • Can be taken with or without food.
  • Generally few side effects compared with other antibiotics.
Downsides
  • While Amoxil (amoxicillin) can be used to treat different bacterial infections, many don't respond to it.
  • Can cause diarrhea, nausea, and vomiting.
  • Except for the extended-release form, you have to take Amoxil (amoxicillin) 2 to 3 times a day, which can be hard to remember.
  • The extended-release form can be more expensive because it's a brand name.
  • Can cause diarrhea.
  • You may need to take Keflex (cephalexin) 2 to 4 times a day, which can be hard to remember.
  • If you're allergic to penicillins or other antibiotics, you might not be able to take this medicine.
Used for
Dosage forms
  • Pill
  • Chewable tablet
  • Extended-release tablet
  • Liquid
  • Pill
  • Liquid
Price
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Reviews
786 reviews so far
62%
saidit'sworth it
45%
saiditworked well
14%
saidit'sa big hassle

Have you used Amoxil (amoxicillin)?

Leave a review
686 reviews so far
64%
saidit'sworth it
48%
saiditworked well
14%
saidit'sa big hassle

Have you used Keflex (cephalexin)?

Leave a review
Side effects
The Amoxil (amoxicillin) FDA package insert doesn’t have numbers about how common side effects are.
The Keflex (cephalexin) FDA package insert doesn’t have numbers about how common side effects are.
Risks and risk factors
  • Interaction with birth control
    • Using oral birth control pills
  • Severe diarrhea
    • Taking Amoxil (amoxicillin) for a long time
  • Severe allergic reaction
    • History of penicillin allergies
  • New infections while taking Amoxil (amoxicillin)
    • Weakened immune system
    • Not taking Amoxil (amoxicillin) correctly
  • Rash
    • Mononucleosis
See more detailed risks and warnings
  • Diarrhea
  • New infections while taking Keflex (cephalexin)
    • Weakened immune system
    • Not taking Keflex (cephalexin) correctly
  • Allergic reaction
    • History of penicillin or cephalosporin allergies
See more detailed risks and warnings