Diphen (diphenhydramine) is an antihistamine used to relieve symptoms of allergies, hay fever (allergic rhinitis), and the common cold. It works by blocking a certain natural substance (histamine) from being produced during the body's allergic reactions.

Relagesic is used to reduce fever, relieve pain, aid sleep, relieve symptoms of allergies or colds,... The drug can cause some serious side effects, so patients need to follow it strictly. doctor's prescription when using the drug.