Anticholinergic side effects commonly include which of the following?

• A. Hyperactivity
• B. Increased salivation
• C. Diarrhea
• D. Dry mouth, constipation, urinary retention

Answer: (D)

Anticholinergic drugs block muscarinic receptors, reducing parasympathetic activity. This leads to drying of secretions and slowed motility in the GI and GU tracts. Dry mouth comes from less saliva production, constipation from decreased intestinal motility, and urinary retention from reduced detrusor contraction and sphincter relaxation. These symptoms are classic for anticholinergic effects. Increased salivation would require parasympathetic activation, and diarrhea would mean increased GI motility—both opposite of what anticholinergics cause. Therefore, dry mouth, constipation, and urinary retention best reflect the anticholinergic side effect profile.