Medically reviewed by Kristie Reed, PharmDKey TakeawaysHydroxyzine can interact with central nervous system depressants, increasing the risk of extreme sedation.Hydroxyzine may cause a heart condition ...

Benadryl (diphenhydramine) is an over-the-counter medication for allergies and cold symptoms. Common side effects include sleepiness, dizziness, dry mouth, and indigestion. Serious side effects are ...