Can anyone give me a quick, and easy way to lose weight?

I am 16, 5ft, 145 pounds. Im just about to take my GCSE's so I dont really have time to do a major workout everyday. Im also epileptic and some of the best drugs for me, they wont allow me to have because they are worried about weight gain. So if anyone can suggest some helpful tips on how to lose weight quickly, or something i can do daily, thats quick then that would be appreciated. Im fully aware that losing weight is never easy and takes some people years. Ive been watching what I eat by doing a food diary, but I admit I could do more exercise.