Anticholinergic Effects of Medicines

Definition: A pharmacologic function or side effect of a medicine that blocks a cholinergic receptor on various types of cells in the body. Anticholinergic effects include a dry mouth, sedation, trouble concentrating, urinary retention, and constipation. Anticholinergic side effects of antihistamines are often used to a person's benefit. This includes taking Benadryl (diphenhydramine) for insomnia and Phenergan (promethazine) for nausea and vomiting. Other medications are specifically designed to have anticholinergic effects as their primary purpose. These include inhaled medicines for COPD such as Atrovent HFA (ipratropium bromide) and Spiriva (tiotropium), which act to open the lungs by relaxing the muscles around the airways, and Nasal Atrovent (iptratropium bromide), which acts to dry up mucus production within the nose.