hello doctor, i m a 19 year old thin girl and for quite sometime like you could say a couple of years i ve been having blackouts that last for about 2 to 3 seconds. initially their frequency was pretty low, like once in 2 to three months. However lately i ve been experiencing them more often. these blackouts they make me feel really dizzy and leave a piercing headache when they re gone. and when i m on my periods i experience them more than twice a day. besides this my eyesight too is getting worse.. though that may be due to my long hours of studying. but what s gotten me worried is that i feel really nauseous and i can t eat anything. I do fel hungry at times but i just can t put food in my mouth. Please advice.