Antibiotics: Common Types, Side Effects & Key Interactions

Most upper respiratory infections are viral. Antibiotics may shorten strep throat confirmed by testing, knock out a UTI, or treat pneumonia when imaging and exam point bacterial cause. Pressuring a clinician for antibiotics “just in case” contributes to resistance that eventually fails when you truly need them.

Diarrhea, yeast infections, and nausea are common. A severe, watery diarrhea with fever after antibiotic use can signal C. difficile — a tough hospital-associated infection that needs specific treatment, not another random antibiotic from the cabinet.

Rifampin speeds liver enzymes that metabolize estrogen contraceptives — backup contraception is recommended. Many antibiotics shift warfarin levels; extra INR checks may be needed. Metronidazole plus alcohol causes a disulfiram-like reaction (nausea, flushing) — skip drinks during treatment and shortly after.