Tag: constipation
Anticholinergic Effects of Antihistamines: Dry Mouth, Constipation, Urinary Issues
Dec, 9 2025
First-generation antihistamines like Benadryl cause dry mouth, constipation, and urinary issues by blocking acetylcholine receptors. These side effects are common, avoidable, and linked to dementia risk in older adults. Switching to second-generation options like Zyrtec or Claritin eliminates these problems.