It is contraindicated for alcohol. So on a technicality it would be inadvisable to imbibe to any significant degree. Having said that, I have drunk alcohol while on that medication but I did pass out in a pub one night well before my normal limit was exceeded, so make sure there is a designated driver in your plan. I advise moderation since Metformin is associated with lactic acid buildup, and if your kidneys are busy getting other substances out of your blood then they may get distracted like mine did.