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What can I do about the metallic taste of Flagyl?

Medically reviewed by Leigh Ann Anderson, PharmD. Last updated on May 8, 2023.

Official answer

by Drugs.com

Metronidazole (brand: Flagyl) can leave a bitter, metallic taste in your mouth. This is a well-known side effect. For many, the bad taste can last throughout treatment, not just when you're swallowing the medicine. Candies, gum, mints or chocolate can be helpful, but may not get rid of the taste completely

Metronidazole side effects are notorious for causing an upset stomach and killing your appetite. For many people, the nausea -- and even vomiting -- can occur just from the bad taste. This bad taste is known medically as "drug-induced dysgeusia"

How can you mask the bad taste?

  • During treatment, have a supply of sweet hard candies (sugar-free, if preferred), gum or mints to help mask the taste.
  • If the bitter taste is only troubling when you're swallowing your medicine, try masking with chocolate, like chocolate pudding or chocolate milk.
  • If you can't tolerate the taste at all, or if you have nausea or vomiting, ask your doctor if there are other options to treat your infection.

The good news is, that for most people, the bad taste will clear up shortly after you finish treatment, which in most cases does not last for more than 7 to 10 days. If you are being treated for the very common sexually transmitted disease (STD) Trichomonas vaginalis ("trich"), a protozoan parasite, your treatment will usually only be one day.

Other medicines are known to affect your sense of taste, such as amoxicillin, diuretics ("water pills"), calcium channel blockers and other blood pressure medications such as the angiotensin-converting enzyme (ACE) inhibitor captopril.

This is not all the information you need to know about Flagyl (metronidazole) for safe and effective use and does not take the place of your doctor’s directions. Review the full product information and discuss this information and any questions you have with your doctor or other health care provider.

Related questions

References
  • Hempel S, Newberry SJ, Maher AR, et al. Probiotics for the prevention and treatment of antibiotic-associated diarrhea: a systematic review and meta-analysis. JAMA 2012; 307:1959–1669. Accessed July 14, 2022 at DOI: 10.1001/jama.2012.3507
  • Flagyl (metronidazole) monograph. Drugs.com. Accessed July 14, 2022 at https://www.drugs.com/flagyl.html
  • Johnson M et al. Metronidazole: An Overview. Up to Date. Accessed May 9, 2023.
  • Dysgeusia. Cleveland Clinic. Accessed May 8, 2023 at https://my.clevelandclinic.org/health/diseases/22047-dysgeusia#

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Does metronidazole treat chlamydia?

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Can you have sex while taking metronidazole?

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