A2. Alli is the brand name of the anti-obesity drug Orlistat which is the main ingredient. It also contains colouring agents which are responsible for the bright blue colour of the capsules. Other ingredients include gelatin (important if you are a vegetarian), sodium starch glycolate, sodium lauryl sulphate (sulphur), talc and titanium dioxide. These capsules do NOT contain caffeine, traces of nuts, gluten or dairy products.