It is very common that a person with sz has to try several different antipsychotics before finding one that works well. I tried Risperdal, Trilafon, Haldol, Seroquel, Abilify, and Geodon and none of them worked very long. But I found that Zyprexa gets rid of all the voices if I take it as prescribed. But none of the antipsychotics should be taken with alcohol -- see if you can convince him that the meds work much better without it. Also note: Invega is a metabolite of Risperdal, so if Invega does not work the chances are that Risperdal will not work for him either. Be prepared also for side effects -- but some people have them and some don't. Zyprexa made me gain weight and I am kind of drowsy much of the time, but I can manage to put up with that most of the time. At least it has given my life back to me. And not all at once -- it may take quite a while for any of the meds to have their full effect. Courage is needed on his part and yours for this to work.
Best wishes,
Carolyn