Antibiotics: how to use them safely and find trusted info

Antibiotics save lives, but they work only for bacterial infections. Ever taken antibiotics for a cold and wondered why you felt worse? Colds and most sore throats are viral; antibiotics won’t help and can cause harm by promoting resistance or side effects. Knowing when to use them keeps you safer and helps the whole community.

When to use antibiotics

Only start antibiotics when a clinician says you need them. Common reasons include bacterial ear infections, strep throat confirmed by test, certain urinary tract infections, and some skin infections. Take the exact dose, finish the full course unless your doctor tells you otherwise, and never share leftover pills. If you’re allergic to penicillin, tell your provider — there are effective alternatives. Watch for allergic signs like hives, swelling, or trouble breathing and get urgent care if those happen.

Buying, alternatives, and safety tips

Shopping online for antibiotics? Use pharmacies with clear contact details, a licensed pharmacist, and a requirement for prescriptions. Avoid sites that sell antibiotics without asking for a prescription — that’s risky. If you’re researching alternatives or need to switch medicines, read our pieces on Augmentin and Flagyl alternatives to see common substitutes clinicians consider. Some drugs interact with foods or alcohol — for example, metronidazole (Flagyl) can cause a bad reaction with alcohol — so check guidance for each antibiotic.

Antibiotic resistance grows when bacteria survive exposure to these drugs. Skipping doses, stopping treatment early, or taking antibiotics for viral illnesses speeds up resistance. Simple habits help: use antibiotics only as prescribed, get recommended vaccines, wash hands, and avoid pressuring clinicians for antibiotics when they aren’t needed.

Side effects vary. Many people get stomach upset, nausea, or yeast infections after antibiotics. Probiotics or plain yogurt can ease mild diarrhea for some people, but ask your clinician first. If you notice severe diarrhea, blood in stools, a high fever, or signs of an allergic reaction, stop the medicine and call your healthcare provider right away.

Special situations matter. Pregnant people, young children, and those with kidney or liver problems may need dose changes or different drugs. Our site has guides that cover common choices and safety checks so you can bring informed questions to your clinician.

Want to dig deeper? Browse the tag list here for articles on safe ordering, alternatives to common antibiotics, and patient guides for specific medicines. If you're unsure about a medication or interaction, contact your clinician or a licensed pharmacist — online info is helpful, but personalized medical advice is best.