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Related to orlistat: Xenical


an inhibitor of gastrointestinal lipases that prevents the digestion, and therefore absorption, of dietary fat, used in the treatment of obesity; administered orally. Because it interferes with the absorption of some fat-soluble vitamins and beta carotene, persons taking orlistat should also take a dietary supplement containing fat-soluble vitamins and beta carotene.
Miller-Keane Encyclopedia and Dictionary of Medicine, Nursing, and Allied Health, Seventh Edition. © 2003 by Saunders, an imprint of Elsevier, Inc. All rights reserved.


Alli, Xenical

Pharmacologic class: GI lipase inhibitor

Therapeutic class: Weight control drug

Pregnancy risk category X


Inhibits absorption of dietary fats in stomach and small intestine


Capsules: 60 mg (over-the-counter drug), 120 mg

Indications and dosages

Obesity management (in conjunction with reduced-calorie diet); to reduce risk of regaining after weight loss

Adults: 120 mg (Xenical) P.O. t.i.d. with each main meal containing fat (during or up to 1 hour after the meal)

Weight loss in overweight adults (in conjunction with reduced-calorie and low-fat diet)

Adults ages 18 and older: 60 mg (Alli) P.O. t.i.d. with each meal containing fat


• Hypersensitivity to drug or its components

• Chronic malabsorption syndrome or cholestasis

• Patients who have had organ transplant or are taking drugs to reduce organ rejection (such as cyclosporine), patients with known problems absorbing food (Alli)

• Pregnancy


Use cautiously in:

• hypothyroidism, nephrolithiasis, diabetes mellitus, clinically significant GI disease, fat-soluble vitamin deficiencies

• history of bulimia or anorexia nervosa

• breastfeeding patients

• children.


• Know that organic causes of obesity should be ruled out before therapy starts.

• Give three times daily with meal containing fat (Alli) or up to 1 hour after a meal (Xenical).

• If patient misses a meal or eats a fat-free meal, omit dose.

• Know that orlistat therapy is frequently combined with psychotherapy.

Adverse reactions

CNS: Xenical: dizziness, headache, fatigue, insomnia, depression, anxiety

EENT: Xenical: ear, nose, and throat symptoms

GI: fecal urgency, flatus with discharge, oily or increased bowel movements, oily spotting, fecal incontinence

GU: Xenical: urinary tract infection (UTI), vaginitis, menstrual irregularities

Hepatic: severe liver injury (rare)

Musculoskeletal: Xenical: back pain, arthritis, myalgia, tendinitis

Respiratory: Xenical: upper or lower respiratory infection

Skin: Xenical: dry skin, rash

Other: Xenical: dental pain, tooth disorder, influenza


Drug-drug. Beta-carotene, fat-soluble vitamins: reduced vitamin absorption

Cyclosporine: reduced cyclosporine blood level (Xenical)

Pravastatin: increased lipid-lowering effects (Xenical)

Warfarin: altered coagulation parameters

Patient monitoring

Monitor hepatic function closely. If liver injury is suspected, discontinue drug immediately and continue to monitor liver function tests.

• Watch for signs and symptoms of UTI, respiratory infection, and EENT disorders.

• Monitor patient for weight loss.

• Evaluate patient's diet for appropriate caloric intake.

• Be aware that patient may develop an elevated urinary oxalate level. Monitor renal function in patients at risk for renal insufficiency.

Patient teaching

• Instruct patient to take with meals as directed. Tell him he may omit a dose if he misses a meal or eats a fat-free meal.

• Advise patient to consume reduced-calorie diet and to spread daily fat intake over three main meals.

• Inform patient that drug predisposes him to EENT, respiratory, and urinary infections. Instruct him to promptly report signs and symptoms.

Instruct patient to report signs or symptoms of hepatic dysfunction (anorexia, pruritus, jaundice, dark urine, light-colored stools, or right upper quadrant pain).

• Tell patient about common adverse GI reactions, including problems controlling bowel movements. If significant GI upset occurs, encourage him to consult prescriber about taking psyllium at bedtime or with each dose.

• Advise patient to ask prescriber if he should take a daily multivitamin containing vitamins A, D, E, K, and beta-carotene at least 2 hours before or after taking drug.

• As appropriate, review all other significant adverse reactions and interactions, especially those related to the drugs mentioned above.

McGraw-Hill Nurse's Drug Handbook, 7th Ed. Copyright © 2013 by The McGraw-Hill Companies, Inc. All rights reserved


A drug, C29H53NO5, that reduces dietary fat absorption by inhibiting the enzyme lipase, used in the management of obesity.
The American Heritage® Medical Dictionary Copyright © 2007, 2004 by Houghton Mifflin Company. Published by Houghton Mifflin Company. All rights reserved.


An agent used to treat obesity, which interferes with pancreatic lipase and allows up to one-third of ingested fat to pass undigested through the GI tract.
Segen's Medical Dictionary. © 2012 Farlex, Inc. All rights reserved.


Xenical® An anti-obesity therapy which interferes with pancreatic lipase, and allows up to13 of ingested fat to pass undigested; orlistat therapy results in a modest–10% loss of weight Adverse effects Loose greasy stools. See Obesity. Cf Olestra.
McGraw-Hill Concise Dictionary of Modern Medicine. © 2002 by The McGraw-Hill Companies, Inc.


A lipase inhibitor that works in the gastrointestinal tract to reduce the body's absorption of fat.
Medical Dictionary for the Health Professions and Nursing © Farlex 2012


An anti-obesity pill that acts in the intestine by inhibiting the action of intestinal fat-splitting enzymes (lipases) so that up to one third of dietary fat is excreted in the faeces. Orlistat was approved by the Food and Drug Administration (FDA) in 1997.
Collins Dictionary of Medicine © Robert M. Youngson 2004, 2005


A drug that inhibits lipase.
Mentioned in: Weight Loss Drugs
Gale Encyclopedia of Medicine. Copyright 2008 The Gale Group, Inc. All rights reserved.
References in periodicals archive ?
The five HFD groups were divided into HFD only (HFDC), HFD with orlistat 15.9 mg/kg body weight and dissolved in ethanol 20 mg/mL (HFD + Orlistat), [23] HFD with MECN at 500 mg/kg (HFD + CN500), HFD with MECN at 1000 mg/kg (HFD + CN1000), and HFD with MECN 1500 mg/kg (HFD + CN1500).
According to Dening, they are now looking to create a synergistic approach to curing obesity with both clay and orlistat. Clay has a huge capacity to soak up fats that come from various foods people eat, while orlistat blocks up to 30 percent of dietary fat digestion and absorption.
Orlistat - currently the only weight-loss drug that doctors can prescribe on the NHS - works by reducing the body's absorption of dietary fat by around a third.
Orlistat is a 'fat binder' that stops fat being absorbed by the body, but it's only prescribed and sold to clinically obese people on a low-fat diet - not those who just need to lose a few pounds.
The development goal of the company's C-103 reformulation is to maintain the proven efficacy of Orlistat while minimising or eliminating the undesirable side effects.
Mice administered with extract dose of 200 mg/kg/bw had a comparable increase in body mass index with mice treated with orlistat (positive control) at day 7 (p > 0.05; Table 2).
Phentermine-topiramate patients were 10 times more likely than patients on placebo to hit the 5% mark at 1 year; liraglutide patients were 5.5 times more likely to do so; naltrexone-bupropion patients were 4 times more likely; lorcaserin patients, 3.1 times more likely; and orlistat patients, 2.7 times more likely to hit the 5% mark.
"The Central Laboratory (CL) of FDA tested the specific batch and was found negative for the presence of the Active Pharmaceutical Ingredient (API), Orlistat," the FDA said.
Closely following the release of Sibutramine, Orlistat (Xenical and Alii) was launched in 1999.
"The drug orlistat, which inhibits fat absorption, is an FDA-approved product," explains Dr.
The only authorized drug for the treatment of obesity is Orlistat that is sold under the trade name Xenical.
In a 20-week, dose-finding, phase II trial, patients with obesity were randomized to liraglutide 1.2 mg, 1.8 mg, 2.4 mg, 3.0 mg or to placebo once daily, or orlistat 3 times daily (TABLE).