I found its the same as on injections. Best advice is know what your drinking, and as stated do a lot of testing. Coctails can be sweet with fruit jucies in so send your b/s sky high, but if you take a correction for it, your in for a hypo later.
As a male, i dont drink coctails, but beer, i know, 2 pints = 1 unit for me, shorts, a dash of full sugar coke helps (but thats a dash) wine acts as it wants to. Just before you drink or just after, try and have some lo GI foods. The breakfast biscuits would be good as you can nibble on them through the night.