I am an mbbs class topper & will be taking my exam in september.but feel short term memory now so need antidepressant which are without side effects?

Sleep and relax: What you need is good sleep and try to relax. Your brain is fatigued. No medicine can help you better than a good plan for next 3 months. Do not let anxiety ruin your progress so far. Stay confident, sleep at least 8h/24 h, eat well, do not forget physical exercise. Talk about your progress with your friends. Good luck with your exam!