List of what causes pharyngitis and conditions for which pharyngitis symptoms are related. If you want to know, "Why do I have pharyngitis?" consider that pharyngitis can be caused by a number of illnesses. This is a list of diseases that pharyngitis is a symptom of, including diseases associated with pharyngitis. What diseases cause pharyngitis? This list features items like Tonsillitis and Common cold. This list of diseases with pharyngitis as a symptom is in alphabetical order with images when available, though it can also be sorted. If you could say "I am experiencing pharyngitis," please consult a physician.