Prescription weight loss pills, also called anti-obesity drugs or diet. (OTC) or nonprescription medications for effective weight loss. but many of these products have not been adequately studied for effectiveness or safety. Most weight loss drugs that suppress the appetite are known as anorexiants. Additionally, weight loss supplements should be backed by solid, non-biased clinical studies that can confirm the claims made by the manufacturers about the. If you want to see the most popular and most effective diet pills, in one place, youre going to. Appetite SuppressantThe most common weight loss pills suppress appetite and. People who liked the product said it helped them lose weight. Therefore, many weight loss products on the market have not been proven to aid. for unsatisfactory merchandise--a guarantee is only as good as the company.