Yes, the B-Vitamins are water soluble, and do not need to be taken with food. The excess will easily dilute from your body via urine. Alcohol inhibits your body's response to the hormone aldosterone, and hinders water absorption in the kidneys. Energy drinks, and 5-hr energy are packed with these B-vitamins as well. In addition, the headache is caused by the meninges of your brain straining to find this supply of B-vitamins that are missing. Dehydration will make you fee like Do-doo, so added water before bed also works well. An ibuprofen before bed is also beneficial, but tylenol should be avoided as the liver metabolizes tylenol.