Phenergan (Promethazine hydrochloride) Reviews:
Common drug rating: 5.00 / Total votes: 1
Feb 27 / 2026
I used Phenergan during a bad allergy flare-up. My sneezing finally calmed down after taking it. The best benefit for me was that my itchy, watery eyes improved a lot, which made it much easier to get through the day.
Is it normal that it makes me feel really sleepy?
Is it normal that it makes me feel really sleepy?

Yes, that’s a common side effect.Phenergan can cause drowsiness because of how it works in the body. If the sleepiness feels too strong or bothers you, talk to your doctor about adjusting the dose or trying another option.