Metronidazole: what it treats and how to use it safely

Metronidazole is a widely used antibiotic that fights certain bacterial and protozoal infections. You’ll see it as pills, a liquid, or a topical cream or gel. It’s common for things like bacterial vaginosis, trichomoniasis, giardiasis, and some dental or skin infections. Knowing the key facts helps you use it right and avoid avoidable side effects.

How people usually take metronidazole

Doctors pick the form and length of treatment based on the infection. For example, bacterial vaginosis often gets a 7-day course of 500 mg twice daily or a single 2 g oral dose in some cases. Trichomoniasis is commonly treated with a single 2 g dose or 500 mg twice daily for 7 days. For giardiasis, many prescribers use 250–500 mg two or three times daily for 5–7 days. Topical metronidazole is used for rosacea or certain skin infections and is applied once or twice daily.

Always follow the exact dose and length your provider gives you. Stopping early can leave some bacteria behind and cause the infection to come back.

Side effects, interactions, and safety tips

Common side effects include nausea, metallic taste, headache, and mild stomach upset. A less common but important issue is a disulfiram-like reaction with alcohol: drinking during treatment or for 48–72 hours after can cause flushing, nausea, and fast heartbeat. Avoid alcohol while taking metronidazole and for the recommended time after finishing.

Metronidazole can interact with blood thinners like warfarin, increasing bleeding risk. It can also affect certain anti-seizure meds. Pregnant people should talk to their doctor — metronidazole is usually avoided in the first trimester unless clearly needed. Breastfeeding people should check with their provider about timing or temporary alternatives.

Store tablets in a cool, dry place. If you miss a dose, take it as soon as you remember unless it’s almost time for the next dose. Don’t double up to catch up.

If you notice severe stomach pain, dark urine, yellowing skin, allergic rash, or signs of a bad reaction, stop the medicine and seek medical help right away.

Want to buy metronidazole online? Make sure the pharmacy requires a prescription, shows clear contact details, has secure checkout (HTTPS), and lists a real pharmacist. Very low prices with no prescription are red flags. Compare generic options, use coupons or discount cards, and read recent user reviews. If you’re unsure about a site, ask your doctor for trusted suggestions.

Metronidazole remains a reliable, affordable option for many infections when used correctly. If you have questions about dosing, side effects, or buying online safely, talk to your healthcare provider or pharmacist — they can point you to legitimate, cost-saving options without risking your health.