premature grey hair!

I am 25 and have just noticed grey hairs appearing rapidly almost as if the hair turns grey overnight! There are not a huge amount of them but they have seemed to have come out of nowhere quickly. My background - I have been taking Sepra which is a sulfa Antibiotic for Acne for 2 years (this is a separate issue i'm trying to resolve) which could be related?. I have had some blood tests on iron and b12 but I didn't know what else to test for. Results showed an iron deficiency but not anemia, b12 was good. I have just started taking a b-complex, iron tablets and copper but am a little concerned that I may be having too much copper (23mg a day). Any suggestions for other courses I could take? Thanks! Tweet