Diet pills and menstruation?

hi, well im 18 and im taking some diet pills while im on my menstrual cycle...do you suggest taking these pills will affect me? is it safe? what can crop up? DIET PILLS CAN MAKE YOUR HEART RACE & THEY ARE WILL DO MORE DAMAGE THAN GOOD.
It might effect you, but im sure you'll be fine just appropriate it as the bottle says and it be ok. If you hold any problems ask you doctor.