Haloperidol is fucking POISON.
Never taken it, never will either. But its dangerously toxic in the longterm. I am absolutely SHOCKED that its still in use.
Ever heard of a poor son of a mother fuck called barry kidston? case of the frozen addicts they called it. Guy was a chemhack that decided to brew up a novel reversed ester version of one of the pethidine type opioids, only he ended up letting a batch get too hot, it underwent an elimination reaction to give the appropriate n-methylphenyltetrahydropyridine, which ends up, once it gets past the blood brain barrier and uptaken into dopaminergic neurons in the substantia nigra, and nigrostriatal tract, that controls movement.
MPTP Gets turned to the tetrahydropyridinium cation MPPP+, stuck inside said cells as its positively charged, and then proceeds to fry the everloving shit out of 'em. Result=permanent, severe, ultra-severe parkinsons disease.
Turns out haloperidol also turns to a similar charged nasty, HPP+, which whilst nowhere near as effective or lethal as MPTP/MPPP+ nevertheless is selectively toxic to the nigro-striatal tract. It WILL cause damage long term. Want refs, just say and I'll provide them to back it up.
Interestingly, loperamide, the antidiarrhea med also forms such a quat nasty. But in its case it appears not to cause damage due to being rapidly spat back out of the BBB by P-glycoprotein.