question about side effects of antipsychotics

[Rainification]

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I was trying to read pharmacology by Dr. Brenner, it mentioned that some of the side effects of antipsychotic drugs, especially the typical ones, such as chlorpromazine, are anticholinergic, antihistamine, and alpha blocker effects. But then later on it mentioned that the treatment of those adverse effects are using drugs like benztropine (which is a anticholinergic) and diphenhydramine (which is an antihistamine with anticholinergic activity)... I'm confused about this, wouldn't those drugs make the side effect even worse?
can someone clearify this, thank you!

 

[AndyRSC]

It's been a long while since I've looked at psych/neuro stuff, but the way I remember it, Ach and dopamine have reciprocal opposition in the brain; dopamine facilitates the initiation of motion, and Ach facilitates stopping / prevents over-responding. A patient on antipsychotics, akin to a Parkinson's patient, has a depression of dopaminergic stimulation, resulting in a higher ratio of cholinergic stimulation and consequent rigidity / movement disorders. For this reason, giving anticholinergics like benztropine reduces dystonia (oculogyric crisis, torticollis, etc) and other extrapyramidal symptoms.

 

[gravitywave]

It's been a long while since I've looked at psych/neuro stuff, but the way I remember it, Ach and dopamine have reciprocal opposition in the brain; dopamine facilitates the initiation of motion, and Ach facilitates stopping / prevents over-responding. A patient on antipsychotics, akin to a Parkinson's patient, has a depression of dopaminergic stimulation, resulting in a higher ratio of cholinergic stimulation and consequent rigidity / movement disorders. For this reason, giving anticholinergics like benztropine reduces dystonia (oculogyric crisis, torticollis, etc) and other extrapyramidal symptoms.

this seems pretty close to the mark. OP, yes neuroleptics are anti-cholinergic but you left out the part about their primary MOA which is anti-dopaminergic. it's those side-effects we're most worried about, and histamines/benztropine help with those to varying degrees.

I find that in general it's best not to go overboard with thinking neuropharm out, other than the autonomics. CNS drugs you just have to memorize; you can get tangled in knots otherwise.