Hello Doc. I was wondering if long term use of benadryl could cause hair loss or hair thinning. I usually take two 25 mg tablets before i go to bed. Sometimes I take three. Also, could taking a large dosage of benadryl have any adverse effects on hair? I was wondering this because i accidentally took two doses(total of 4 25mg pills)in the span of an hour. This is a really great website. Thanks.
I’ve not heard of any connection between Benadryl (diphenhydramine) and hair loss. Antihistamines like diphenhydramine are not known to cause any kind of hair loss, even at higher dosages. There could always be exceptions, but I doubt you’ll see a problem.