What antihistamines work the fastest and are most effective ? with the tablets do you chew them or take with water ?

Hard to say: Some antihistamines are more effective in some people then others.You really cannot say that one is better than the other. It's just a matter of trial and error. I would suggest you swallow the pills with water brother then chew them. There used to be a chewable form of Claritin (loratadine) although I do not know if it is available any longer.Some antihistamines will make you more sleepy than others.

Antihistamines: Most antohistamines work wothin 30-45 minutes, if taken orally it does not speed their effect, either chewed or swallowed, mit is faster if given intravenous.