Most side effects are related to the way you take the product and how much fat you consume when taking alli. Not everyone experiences GI side effects (or “treatment effects”), but they can be manageable when you follow a reduced-calorie, low-fat diet.

All drugs can have side effects and you should check with your doctor if anything unusual or severe occurs when using any weight-loss product. In controlled trials, only about 5% of subjects on alli dropped out due to treatment effects. In fact, anecdotally, many users have told us that treatment effects served as a signal that helped them adopt healthier eating patterns.

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No. alli is nonsystemic acting and won’t affect the central nervous system. You will not feel the same jitteriness or palpitations from the drug.

There has been no evidence in the clinical trials that indicates that it causes a problem. If you experience sleep problems, please see your doctor.

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There is no conclusive scientific evidence that fiber will reduce the treatment effects of alli, although fiber has many benefits to your body. However, eating a reduced-calorie, low-fat diet will help to manage treatment effects.

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Treatment effects are bowel movement changes that are most commonly caused by eating meals with too much fat while using alli capsules. Such effects may include oily spotting, loose stools and more frequent stools that may be hard to control.

alli works by blocking the absorption of a quarter of the fat in the foods you eat. This undigested fat passes through the body naturally and it is not harmful. In fact, you may recognize it in the toilet as something that looks like the oil on top of a pizza.

Eating a low-fat diet that consists of 15 grams of fat per meal on average can lower the chance of experiencing these treatment effects.

Additionally, the alli program can help you reduce the likelihood of having treatment effects. For example, when you purchase alli, you receive educational booklets, which help you transition to a healthy lifestyle. You’ll also receive access to myalliplan™, an individualized, online support program created by weight-loss experts, where you can get recipes and meal plans for low-fat meals.

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To report an adverse event or side effect as a result of using alli capsules, please call 1-800-671-2554, M-F, 9 a.m. – 4:30 p.m. ET so we can give you personalized attention. In the event of a medical emergency, please contact your doctor, local emergency facility, or local poison control center.

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