Can you take hydrocodone and benadryl (diphenhydramine) at the same time?

Yes, but caution: Benadryl (diphenhydramine) can be used with hydrocodone to decrease itching and nausea that sometimes happens with hydrocodone. Benadryl (diphenhydramine) and hydorocodone, however, are both sedating and together cause additive drowsiness. Also both drugs independently can cause constipation and urinary hesitancy, so taken together these problems also can be worse. Be careful and discuss with your doctor.

Yes, but beware.: Beware that the combination may make you very sleepy and cloud your judgement.