Benadryl (diphenhydramine) can have serious side effects in high doses or if taken regularly.

Benadryl or Diphenhydramine is a very commonly used over-the-counter medication used for allergies, insomnia (it is in many sleep aids) and even anxiety. It is relatively safe when taken in typical and directed doses. However, side effects can include dry eyes, dry mouth, constipation, dehydration, erectile dysfunction, urinary retention (leading to urinary tract infections), seizures, blood cell abnormalities and even irregular heart rhythms leading to death. If you take this medication regularly, talk to your provider about risks, benefits, and any potential side effects.

Dr. Pagnani is the Medical Director of Rittenhouse Psychiatric Associates in Philadelphia, an Instructor at The Johns Hopkins Hospital and he supervises psychiatric residents at Jefferson Hospital. www.RittenhousePA.com or visit  @RittenhousePsych  for 100's of educational mental health videos.