If someone is allergic to codeine, would it be okay to take hydrocodone?

Maybe...: This generally depends on what kind of reaction you had to codeine. I don't usually recommend you take hydrocodone if you had a severe allergic reaction (i.e., hives, swelling, difficulty breathing, etc.). One thing about codeine, however, is that it can cause itching as a side effect, and this isn't necessarily an allergy. If that's all that happened, you may be able to try it. Talk to your dr.