What are the signs of an allergic reaction to fetonyal and is nthere anything that you can do at home to ease those symptoms?

What you want to fear is dying from an overdose. What some call the final allergy.

You should not take any form of this medication if you are allergic to it, especially if you talk about the street drug. For local rash +/- itching due to the patch, steroid cream OTC or prescribed strength can be used as needed. DO NOT EVER TAKE STREET DRUG FENTANYL. Take care.