How can I tell if I have depression or if its just caused by porphyria?

Answer 1

Well since depression and psychiatric changes are a symptom of the disease i imagine it could be both. Being sick all the time is known to cause depression. Compounded by the fact that its already a symptom of porphhyria.
Speak to you doctor about your concerns. Get a second or third opinion if you don't feel you are being heard or treated properly.