Anticholinergic effects of antipsychotics include which of the following?

• A. Tremor and rigidity
• B. Fever
• C. Diaphoresis
• D. Dry mouth and constipation

Answer: (D)

Anticholinergic effects come from blocking muscarinic acetylcholine receptors, which reduces parasympathetic activity. When this happens, glands produce less saliva and the GI tract slows down, leading to dry mouth and constipation. The other options reflect different mechanisms: tremor and rigidity are extrapyramidal symptoms from dopamine blockade in the nigrostriatal pathway, not muscarinic blockade; diaphoresis (sweating) is a cholinergic process, and anticholinergic drugs actually reduce sweating; fever isn’t a direct anticholinergic effect and would point to other processes like infection or neuroleptic-related hyperthermia rather than a classic anticholinergic side effect. So dry mouth and constipation best illustrate anticholinergic effects.