From the FDA Drug Label
Mouth: A sharp, unpleasant metallic taste is not unusual. A modification of the taste of alcoholic beverages has also been reported. The drug that most commonly causes altered taste is metronidazole (PO), as it can cause a sharp, unpleasant metallic taste and a modification of the taste of alcoholic beverages 1.
From the Research
The drug that most commonly causes altered taste is metronidazole, as evidenced by its widespread use and association with taste disturbances in various studies, including a 2020 review of oral adverse effects of drugs 2. This antibiotic is known for producing a metallic taste in the mouth that patients often describe as unpleasant. Other medications frequently associated with taste disturbances include certain antibiotics like clarithromycin and tetracyclines, ACE inhibitors such as lisinopril and captopril, and chemotherapy agents. The mechanism behind drug-induced taste alterations varies but often involves direct effects on taste receptors, secretion of the drug into saliva, disruption of taste receptor cell turnover, or effects on neural transmission of taste signals. These taste changes typically resolve after discontinuation of the medication, though the timeline varies depending on the specific drug. Some key points to consider include:
- Metronidazole's efficacy in treating bacterial vaginosis and trichomoniasis, as discussed in a 2015 expert opinion on pharmacotherapy 3
- The potential for metronidazole to cause taste disturbances, as noted in a 2009 study on the comparison of oral and vaginal metronidazole for treatment of bacterial vaginosis in pregnancy 4
- The importance of staying well-hydrated and practicing good oral hygiene to minimize taste disturbances while taking medications, as suggested by various studies, including a 2020 review of oral adverse effects of drugs 2. Patients experiencing significant taste alterations should discuss this side effect with their healthcare provider, as dosage adjustments or alternative medications may be available. In general, the treatment of bacterial vaginosis and other conditions with metronidazole should be guided by the most recent and highest-quality evidence, such as the 2020 review of oral adverse effects of drugs 2.