Compare Penicillin vs. Bactrim

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

Kills bacteria.

Penicillin Vk (Penicillin) is good for treating many bacterial infections and is available as a generic. You may need to use another form of birth control along with your birth control pills. It's also best taken on an empty stomach but it can cause an upset stomach.

3.9/ 5 average rating with 1297 reviewsforPenicillin
Kills bacteria.

Bactrim (sulfamethoxazole / trimethoprim) is good for treating many bacterial infections and is available as a generic. However, you can be more likely to sunburn.

3.6/ 5 average rating with 473 reviewsforBactrim
Upsides
  • Available in generic.
  • Available in different forms: tablet, capsule and suspension.
  • Used to treat many types of bacterial infections.
  • Widely available as a generic product and in a variety of formulations (tablet, capsule, suspension).
  • Works well to treat many types of bacterial infections
Downsides
  • Many bacteria have developed resistance. Your doctor may run tests to see if Penicillin will work on your infection.
  • Can make birth control pills less effective.
  • Best taken on an empty stomach, but can cause stomach upset and diarrhea.
  • Makes you sensitive to the sun.
  • Can upset your stomach
  • Drink plenty of water or fluids to avoid harming your kidneys
  • May cause birth defects
Used for
Dosage forms
  • Pill
  • Pill
  • Liquid
Price
No pricing information available
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Reviews
1297 reviews so far
71%
saidit'sworth it
52%
saiditworked well
12%
saidit'sa big hassle

Have you used Penicillin Vk (Penicillin)?

Leave a review
473 reviews so far
59%
saidit'sworth it
49%
saiditworked well
22%
saidit'sa big hassle

Have you used Bactrim (sulfamethoxazole / trimethoprim)?

Leave a review
Side effects
The Penicillin Vk (Penicillin) FDA package insert doesn’t have numbers about how common side effects are.
The Bactrim (sulfamethoxazole / trimethoprim) FDA package insert doesn’t have numbers about how common side effects are.
Risks and risk factors
  • Diarrhea
  • Decreased effectiveness of birth control pills
  • Allergic reactions
    • Prior severe allergic reaction to Penicillin Vk (Penicillin)
See more detailed risks and warnings
  • Diarrhea
  • Sunburn
  • Rash
  • Harm to fetus
  • Lower kidney function
    • Elderly
    • Taking other medicines that lower kidney function
See more detailed risks and warnings