hi. haldol can be rough. some people get low mood, even straight up depression, from just about any tranquilizer/antipsychotic, old or new. Haldol is one of the more toxic, older drugs. it -is- effective against psychosis, mania, agitation, etc., but...not my cup of tea, personally.

i dont know your situation, but could you see about tapering the haldol? dosage can also be an issue. back in the day, the tendency was to use high doses of the tranquilizers, especially the high potency ones, such as haldol and prolixin. now, with brain imaging data and such available, it seems that the vast majority of people don't need high dose tranquilizers.

hope this helps. of course, there's always psychosocial factors to consider, stress, etc.