What are some side effects of benadryl (diphenhydramine) on your body?

Benadryl (diphenhydramine) can cause : Sedation the nxt day (due to its long1/2-life). Can cause decreased alertness, diminished cognitive function, delirium, dry mouth, blurred vision, urinary retention, constipation, increased intraocular pressure/glaucoma, & many other anticholinergic agent. Ill effects in disease specific states & drug-drug interaction are other concerns. Generally safe when used in moderation for the right purpose.