Most pills which are claimed to enhance the breasts are herbal formulations and generally consist of traditionally used herbs which have been widely used for many centuries. There do not appear to be any great risks from using such well known herbs, although the way that the body responds to any substance is very individual and can vary a great deal from one person to another. Some women using breast enhancement pills feel that they have experienced some ill effects, such as unwanted weight gain, acne or menstrual irregularities. On the other hand many women have claimed the opposite effects, that a side effect of such products is assisting weight loss, clearing acne or solving menstrual irregularities. People have to find out for themselves how exactly they react to such herbs, but as they are standard products in health food stores these herbs would appear to be generally beneficial to your health rather than a risk to your health.