Common Antibiotic Dosing Calculator

Completing the full course ensures all bacteria are killed, reducing the risk of antibiotic resistance. Stopping early when you feel better may leave resistant bacteria alive, making future infections harder to treat. However, recent evidence suggests shorter courses may be adequate for some infections — follow your doctor's instructions.

Narrow-spectrum antibiotics (like penicillin) target specific bacteria, while broad-spectrum ones (like amoxicillin-clavulanate, fluoroquinolones) target many types. Narrow-spectrum is preferred when the causative bacteria is known, to minimize disruption to normal gut flora and reduce resistance development.

It depends on the antibiotic. Metronidazole (Flagyl) and tinidazole cause severe nausea with alcohol. Most other antibiotics don't have a direct interaction, but alcohol can impair immune function and hydration. It's generally best to avoid alcohol until you've recovered and completed treatment.