Acute psychoses and confusion can be caused by concurrentuse of metronidazole and disulfiram
Clinical evidence,mechanism, importance and management
In a double-blind study in 58 hospitalised chronic alcoholics taking disulfiram,29 patients were also given metronidazole 750mg daily for a month, then 250mg daily thereafter. Six of 29 subjects in group receiving metronidazole developed acute psychoses or confusion. Five of 6 had paranoid delusions and in 3 visual and auditory hallucinations were also seen. The symptoms persisted for 2 to 3 days after drugs were withdrawn, but disappeared at end of a fortnight and did not reappear when disulfiram alone was restarted (See reference number 1). Similar reactions have been described in two other reports (See reference number 2,3).
The reason for this interaction is not understood,but it appears to be established. Concurrent use should be avoided or very well monitored.
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