Metronidazole inhibits aldehyde dehydrogenase and causes acetaldehyde to accummulate in the bloodstream. A disulfiram like reaction occurs when consuming alcohol and the patient may complain of symptoms such as facial flushing, throbbing headache and palpitations. A patient taking metronidazole orally should abstain from drinking alcohol while taking metronidazole and for 48 hours after stopping it.
Uncommonly, reactions have been reported whilst using vaginal metronidazole.
Last reviewed 01/2018