Alli is an effective weight loss medication specifically designed for overweight adults. Available in two strengths, 60 mg and 120 mg, Alli uses Orlistat as its active ingredient to help block the absorption of dietary fats. This makes it a helpful aid in managing weight when used in conjunction with a reduced-calorie, low-fat diet. Manufactured by reputable companies, Alli is also recognized under various brand names, including Slim Trim Active, Reeshape, and Xenical.