Is it safe to drink alcohol while on Metronidazole?

Dear Ask The Doctor: Hi was given metronidazole yesterday only took 1 200mg yesterday, have not took any today due to side effects, is it safe to have an alcholic drink this evening 27 hrs have passed since i took the tablet, want to triple check as 3 chemists have said its fine to drink

Dear Sarah: Metronidazole is an antibiotic drug used to treat bacterial infections. There are some points to bear in mind while on this treatment. Metronidazole is believed to have the ability to block the body's breakdown of alcohol, leading to an accumulation of a substance called acetaldehyde in the bloodstream leading to a disulfiram like reaction. The effects are nausea, vomiting, tachycardia, shortness of breath, intense flushing and headache.

Although there has been little in the way of published pharmacological evidence to support this interaction with alcohol, I would suggest that you avoid alcohol for at least 72 hours after completing the treatment with metronidazole.