I think that there are two points about the alcohol.
Firstly as others have said, there probably is not much worry mixing the metformin with a bit of alcohol; the SPC from the EMA states that alcohol intoxication can precipitate lactic acidosis; so avoid intoxication, as we all should.
Secondly, alcohol can drop the glucose a bit, even 8 hours after the last drink - this is not a problem on metformin, cos the glucose levels do not go too low, but is a problem if on insulin or sulphonylurea (when one would be advised to have a snack with a moderate amount of alcohol)
10 units alcohol twice per week is a moderate amount on these two nights, but I guess you take care afterwards.
Best wishes
Firstly as others have said, there probably is not much worry mixing the metformin with a bit of alcohol; the SPC from the EMA states that alcohol intoxication can precipitate lactic acidosis; so avoid intoxication, as we all should.
Secondly, alcohol can drop the glucose a bit, even 8 hours after the last drink - this is not a problem on metformin, cos the glucose levels do not go too low, but is a problem if on insulin or sulphonylurea (when one would be advised to have a snack with a moderate amount of alcohol)
10 units alcohol twice per week is a moderate amount on these two nights, but I guess you take care afterwards.
Best wishes