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A member asked:

Benadryl (diphenhydramine) tabs take about 1 hour to start working to treat my allergic reaction (rash) would benadryl (diphenhydramine) im be a faster alternative? can i obtain an rx?

A doctor has provided 1 answer
Dr. John Chiu answered

Depends: Benadryl (diphenhydramine) may help hives but not a rash which has lasted more than 24 hrs. IM Benadryl (diphenhydramine) gives you perhaps a 30-minute head start vs oral = not worth the cost or hassle. If you have throat swelling , you may need adrenaline and an allergy consult since this can be life-threatening.

Answered 11/13/2015

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