No, don't drink alcohol while taking metronidazole (or tinidazole) for trichomoniasis. Combining either drug with alcohol can trigger a disulfiram-like reaction: flushing, nausea, vomiting, headache, and a racing heart. Skip alcohol during the full course of metronidazole, and stay off it for a stretch after finishing tinidazole, since it lingers longer CDC, 2021.
with the right treatment
testing, not symptoms, decides
| Item | Value |
|---|---|
| Curable? | yes — with the right treatment |
| Tested by | NAAT / lab |
| Often | no symptoms |
| If you may have it | get tested — testing, not symptoms, decides |
Why alcohol and metronidazole don't mix
Metronidazole and tinidazole are nitroimidazole antibiotics, the standard cure for trichomoniasis, the infection caused by the protozoan parasite Trichomonas vaginalis CDC. Both drugs can interfere with how your body breaks down alcohol. Normally your liver clears alcohol in two steps; these drugs appear to stall the second step, letting a toxic byproduct called acetaldehyde build up. That buildup produces the disulfiram-like reaction, named after disulfiram, a medication once used to deter drinking by making people feel sick when they drank.
A drink during treatment can leave you flushed and hot in the face, queasy or actively vomiting, headachy, and aware of your heart pounding. It's unpleasant, and usually not dangerous, but there's no reason to gamble on how strong your own reaction will be. Don't drink any alcohol while the drug is in your system.
How long to wait differs by drug. With metronidazole, abstain for the whole course and a little while after your last dose. Tinidazole stays in the body longer, so the wait after your final dose is longer too. Watch for hidden alcohol in mouthwash, cough syrups, and some tinctures, since a few people react to those as well.
How trichomoniasis is treated
Treatment is a defined course of oral antibiotics, and the recommended regimen now differs by sex. For women, current guidelines favor metronidazole 500 mg by mouth twice daily for 7 days. For men, the standard is metronidazole 2 g by mouth as a single dose. Tinidazole 2 g as a single oral dose is an alternative for either. You can read the full breakdown on our trichomoniasis treatment page.
Guidelines moved women off the old single 2 g dose because a multi-day course works better. In a randomized trial, about 19% of women given the single dose were still infected at follow-up, versus about 11% on the 7-day course, roughly half the retest-positive rate Muzny et al.. That difference changed the guideline.
What treatment is actually like
It's a short, ordinary course of pills. Finish every dose even after symptoms fade. People who stop early because they feel better commonly end up still infected. Some people get a metallic taste or mild stomach upset; taking the pills with food helps. And no alcohol until the drug clears, which for the 7-day course means the whole week plus a buffer afterward.
Trichomoniasis is the most common curable non-viral STI in the US, with an estimated 2.6 million infections, and over 80% of diagnosed cases are in women Sex Transm Dis, 2018. Clinics handle it daily.
Do partners need treatment?
Yes, treat all sex partners at the same time, whether or not they have symptoms. If only you're treated, an untreated partner can hand the infection right back. This back-and-forth, called reinfection, is the single biggest reason a "cured" case reappears. Ask your clinician about treating partners concurrently; many will provide medication or a prescription for partners without a separate visit where it's allowed. Avoid sex until everyone has finished treatment and symptoms have resolved.
Follow-up and retesting
Because reinfection is so common, current guidance recommends that sexually active women get retested about 3 months after treatment. The drug rarely fails, but re-exposure does happen. This isn't the same as a test-of-cure right after finishing pills. If symptoms persist or return sooner, get checked again rather than assuming the medication didn't work. Our trichomoniasis testing & diagnosis page explains how the follow-up sample works.
What happens if it's left untreated
Untreated trichomoniasis doesn't just linger; it raises real risks. It increases the chance of getting or passing other sexually transmitted infections, including HIV, because the inflammation it causes makes tissues more vulnerable. In pregnancy, it's linked to preterm birth (delivery before term, which carries health risks for the baby) and low birth weight (a baby born smaller than expected, also tied to complications). Persistent infection can also keep symptoms going: the irritation, odor, and abnormal trichomoniasis discharge that often bring people in. If unusual discharge is what's worrying you, see our guide to trichomoniasis discharge.
How testing usually works
Most cases are diagnosed from a simple sample, a urine cup, a self-collected swab, or a quick exam, with results usually back in a few days. Testing is free or low-cost at many health departments, Planned Parenthood, and Title X clinics. If you've had a recent exposure and aren't sure when to check, our when to test after exposure guide explains the timing. When you're ready, you can get tested, and you can compare testing providers to find one that fits your budget and privacy needs.
Preventing trich going forward
Correct, consistent condom use every time lowers your risk, and routine screening of at-risk groups catches infections that have no symptoms at all. Trichomoniasis is often silent, especially in men, so testing finds it before it spreads. Treating partners together and finishing your own course rounds out the picture.
- Use condoms correctly and every time you have sex.
- Get screened if you're in an at-risk group or have a new or multiple partners.
- Treat all current partners at the same time you're treated.
- Skip alcohol until your full course of metronidazole or tinidazole has cleared.
When to see a clinician
Get checked if you have abnormal discharge, itching, irritation, pain with sex or urination, or you've learned a partner has trichomoniasis. See someone promptly if you're pregnant and may have been exposed, or if symptoms persist or return after treatment. And if you drank alcohol on metronidazole or tinidazole and feel severely ill, with repeated vomiting, chest tightness, or a sense that something is very wrong, seek care.
Comparing the two treatment drugs
| Feature | Metronidazole | Tinidazole |
|---|---|---|
| Women's regimen | 500 mg twice daily for 7 days (preferred) | 2 g single dose (alternative) |
| Men's regimen | 2 g single dose | 2 g single dose (alternative) |
| Alcohol rule | Avoid during the course and shortly after | Avoid during and for a longer window after (stays in the body longer) |
| Reaction risk | Disulfiram-like reaction | Disulfiram-like reaction |