Cocaine is really not that bad for the body (Outside the stress on your heart during use), but it's is bad for your neurochemical balance. Like many drugs it can be used infrequently without much issue, but it messes you up with regular use.

UK always seems to go hard with drugs. I don't know if they as a society just tolerate being hung over more, or if they biologically don't feel it a badly. Liquor, MDMA, Speed, Coke, I don't know how those fuckers manage to indulge so hard and make it to work the next day.