My doctor prescribed me 2 doses of 1 gram of flagyl to treat trick. When would side effects occur after taking dosage? 

Also how long after last dose before using any alcohol products?

The recommended dose of metronidazole (Flagyl) for treatment of trichomoniasis is a single 2 gram dose taken by mouth, not two separate 1 gram doses taken at different times.  The most common side effect following this is mild gastrointestinal upset.  Fewer than 1 in a thousand (and probably closer to 1 in 10,000) adults who consume alcohol within 24 hours of taking metronidazole will experience vomiting as an adverse effect of taking alcohol and the medication.

I hope this information is helpful.  EWH

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