What are the side effects of taking Unisom?

Unisom, which is a brand name for the sedative antihistamine doxylamine, can cause a variety of side effects due to its action on histamine receptors in the body. Common side effects include drowsiness, dry mouth, constipation, blurred vision, and dizziness, which occur because the drug depresses the central nervous system and blocks acetylcholine. Some individuals may also experience gastrointestinal disturbances such as nausea or upset stomach. Less frequently, one might encounter more severe reactions such as confusion, urinary retention, or an irregular heartbeat. It is important to be aware that since Unisom is intended to induce sleep, its drowsiness effect can often be quite potent; therefore, activities requiring alertness should be avoided after taking the medication. If any severe or persistent side effects are experienced, a healthcare professional should be consulted.