Hello Dr, Thank you for asking at HCM. There are various types of allergic reactions to drugs like skin reactions, GI reactions, etc. There are various types of skin reactions as well. Generally speaking, among the drugs that you have mentioned, Norfloxacin and Esomeprazole could be causing allergic reaction. However, please note that none of the four the most common allergy causing drugs (for example, penicillins, cephalosporins, NSAIDs, etc). Also, to complicate the picture, sometimes not drugs themselves but additives/coloring agents/non-drug components within the drug formulation can also cause allergic reaction. Hope above information will be helpful to you. Thank you & Regards.