Deedee asked
My daughter has been prescribed cyproheptadine today, and I had already given her benadryl earlier today for an itchy rash. She is 6 and the dose of cyproheptadine is 1 tsp. Is it safe her to take it so close to the Benadryl? And is this a safe drug to give my child?
Answer
While Benadryl (diphenhydramine) and cyproheptadine (brand name Periactin) should not be taken at the same time, they can be used together in the same day, just separated by at least 8 hours. Both medications are similar in their effect and are both classified as antihistamines.
Benadryl, a commonly used first generation antihistamine, is beneficial not only for allergy symptoms but also for the treatment of insomnia. It generally causes pronounced sedation about 30 minutes to 1 hour after taking by mouth and is a popular over the counter sleep aid.
Cyproheptadine, while classified as an antihistamine, has unique propterties. Not only does it act as an antihistamine (very effectively in that regard), it also has serotonin blocking (i.e. antagonizing) effects. This makes it potentially beneficial for a variety of indications including vascular headaches and for appetite stimulation.
As Benadryl and cyproheptadine are similar medications, and due to the fact that use of both together may have additive side effects, they should not be used at the same time. After taking by mouth, cyproheptadine reaches peak concentrations in the blood in about 6 to 9 hours. The average duration of action is about 8 hours. Therefore, doses of Benadryl and cyproheptadine should be separated by at least 8 hours.
