Is it permitted to drink before prayer?

Hello, It is forbidden to drink before Shacharit prayer, except for water (Shulchan Aruch, Orach Chaim, siman 89, se'if 3). It is also permitted to drink coffee with sugar or tea with sugar, and it is proper to be stringent not to drink coffee mixed with milk. In any case, those who are lenient in this as well have whom to rely on (Responsa Yabia Omer, part 4, Orach Chaim, siman 12). The prohibition against drinking before prayer begins at alot hashachar, unless it is an intoxicating drink; in that case, one should be stringent not to drink more than the amount of a kebeitzah half an hour before alot hashachar (see Mishnah Berurah, siman 89, se'if katan 27, and siman 232, se'if katan 35, and Halacha Berurah, siman 89, se'if 28). 

With blessing, Hillel Meirs