What Causes Headache While Suffering From Optic Neuritis?

hi, i ve been told i have, optic neurtis, early stages of M.S and a a small left posterior communicating arterty aneurysm of 1.4mm diamaeter. I am suffering from headaches some much worse than others. The problem i now face is that none of the specialist i m am seeing will state what is causing the headaches and i therefore can take no medication. I m now stuck, with no medication to take please can you advise. I m 31,5ft 2, appox 9 stone in weight and have had no other ill health pri to this