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    DEA Class;  (Rx OTC)

    Common Brand Names; Alli, Xenical

    • Gastrointestinal Agents, Other

    Gastrointestinal lipase inhibitor; non-systemically blocks dietary fat absorption; causes weight loss and limits weight regain; significant GI side effects
    By prescription, indicated for obese adults and adolescents 12 years and older with a BMI 30 kg/m2 or more OR those with a BMI of 27 kg/m2 or more with 1 or more obesity-related risk factors
    Non-prescription product used to help promote weight loss in overweight adults

    Obesity Management

    Indicated in patients with pretreatment BMI >30 kg/m², or BMI >27 kg/m² in presence of other risk factors or diseases (eg, HTN, DM, hyperlipidemia)


    Chronic malabsorption syndrome



    • Oily spotting (5%)
    • Flatulence
    • Fatty/oily stool
    • Increased defecation
    • Fecal incontinence
    • Nausea
    • Vomiting
    • Reduced absorption of fat soluble vitamins and beta-carotene
    • Liver failure
    • Oxalate nephropathy
    • Leukocytoclastic vasculitis

    If a meal is missed or contains no fat, dose should be omitted

    Daily fat intake (30% of calories), carbohydrate, and protein should be evenly distributed over 3 main meals

    Multivitamin supplement (including vitamin A, D, E, K) is recommended; supplement should be taken once a day at least 2 hours before or after the administration of orlistat, such as at bedtime

    Postmarketing reports of severe liver injury with hepatocellular necrosis or acute hepatic failure with some cases resulting in liver transplant or death; patients should be instructed to report any symptoms of hepatic dysfunction (anorexia, pruritus, jaundice, dark urine, light-colored stools, or right upper quadrant pain) while receiving therapy; when these symptoms occur, this and other suspect medications should be discontinued immediately and liver function tests and ALT and AST levels obtained

    Some patients may develop increased levels of urinary oxalate following treatment; cases of oxalate nephrolithiasis and oxalate nephropathy with renal failure reported; monitor renal function when prescribing therapy to patients at risk for renal impairment and use with caution in those with a history of hyperoxaluria or calcium oxalate nephrolithiasis; discontinue therapy in patients who develop oxalate nephropathy

    Substantial weight loss can increase risk of cholelithiasis

    Exclude organic causes of obesity (eg, hypothyroidism), before prescribing therapy

    May increase gastrointestinal events when taking a diet high on fat (>30% total daily calories from fat)

    Pregnancy Category: X; weight loss offers no potential benefit to a pregnant woman and may result in fetal harm; a minimum weight gain, and no weight loss, is currently recommended for all pregnant women, including those who are already overweight or obese

    Lactation: Not recommended; not known if orlistat is distributed in breast milk


    360 mg/day PO (Xenical, Rx-only), 180 mg/day PO (Alli, OTC use).


    360 mg/day PO (Xenical, Rx-only), 180 mg/day PO (Alli, OTC use).


    360 mg/day PO (e.g., Xenical, Rx-only); OTC use (e.g., Alli) not recommended.


    12 years: 360 mg/day PO (Xenical, Rx-only); OTC use (i.e., Alli) not recommended.
    1 to 11 years: Safety and efficacy have not been established.


    Not indicated.



    • 60mg (Alli)
    • 120mg (Xenical)