Ive had 4 nights out on the drink while in ketosis and im still here lol. I think if you want to drink alcohol its best to eat something before hand (which i always do) and the next day. It also depends if you can get straight back on 100% it is hard and its ruined one of my weeks (see my weigh in list below) you just have to decide for your self. I drink vodka lime and soda DO NOT drink wine!!! i put on loads that week cos i had wine not vodka.