Xenical

Xenical (orlistat 120 mg) is a prescription-only lipase inhibitor indicated for obesity management in conjunction with a reduced-calorie diet. It functions by inhibiting the absorption of dietary fats in the gastrointestinal tract, providing a mechanistically distinct approach to pharmacologic weight reduction. This agent is suitable for adults with a body mass index (BMI) of 30 kg/m² or greater, or 27 kg/m² or greater in the presence of other risk factors such as hypertension, type 2 diabetes, or dyslipidemia. Treatment should be viewed as part of a comprehensive weight-management strategy that includes dietary modification, physical activity, and behavioral change.

Features

• Active ingredient: Orlistat 120 mg
• Pharmaceutical class: Lipase inhibitor
• Presentation: Turquoise blue hard gelatin capsules
• Pack sizes: 21, 42, or 84 capsules
• Mechanism: Acts locally in the GI tract to inhibit gastric and pancreatic lipases
• Prescription status: Rx-only medication
• Manufacturer: Genentech USA, Inc. (a member of the Roche Group)

Benefits

• Achieves clinically significant weight loss when combined with a hypocaloric diet
• Reduces absorption of dietary fat by approximately 30%
• Improves obesity-related comorbidities including glycemic control in type 2 diabetes
• Lowers LDL cholesterol and total cholesterol levels independent of weight loss effects
• Provides a non-systemic mechanism of action with minimal absorption
• Supports long-term weight maintenance when used as part of comprehensive management

Common use

Xenical is indicated for obesity management in adults with an initial body mass index (BMI) ≥30 kg/m², or ≥27 kg/m² in the presence of other risk factors (e.g., hypertension, diabetes, dyslipidemia). Treatment should be discontinued if patients fail to achieve at least 5% weight loss after 12 weeks of therapy. The medication is intended as an adjunct to a medically supervised reduced-calorie diet and should be accompanied by a nutritionally balanced eating plan containing approximately 30% of calories from fat.

Dosage and direction

The recommended dose is one 120 mg capsule taken three times daily with each main meal containing fat (during or up to 1 hour after the meal). Doses may be omitted if a meal is missed or contains no fat. The capsule should be swallowed whole with water. Patients should distribute their daily fat intake evenly across three main meals. Maximum daily dosage should not exceed 360 mg (three capsules). Treatment duration beyond two years has not been systematically studied.

Precautions

Patients should be advised to follow a diet with no more than 30% of calories from fat to minimize gastrointestinal adverse effects. Fat-soluble vitamin (A, D, E, K) levels should be monitored, and supplementation may be required—take vitamins at least 2 hours before or after Xenical administration. Use with caution in patients with history of hyperoxaluria or calcium oxalate nephrolithiasis. Not recommended for use in pediatric patients. Monitor for any signs of hepatic injury. Pregnancy should be excluded before initiation and adequate contraception maintained during treatment.

Contraindications

Chronic malabsorption syndrome or cholestasis. Known hypersensitivity to orlistat or any component of the formulation. Patients with organic causes of obesity. Concurrent use with cyclosporine. Pregnancy and breastfeeding. Anorexia nervosa or bulimia nervosa.

Possible side effects

Gastrointestinal events are most common and include: oily spotting, flatus with discharge, fecal urgency, fatty/oily stool, oily evacuation, increased defecation, and fecal incontinence. These effects are generally mild to moderate, decrease with continued use, and are associated with high-fat meals. Other reported effects: headache, upper respiratory infection, hypoglycemia in patients with diabetes, tooth/gum disorder, rectal pain/discomfort. Rare cases of severe liver injury have been reported.

Drug interaction

May reduce absorption of fat-soluble vitamins (A, D, E, K) and beta-carotene—supplementation recommended. May decrease plasma levels of cyclosporine—avoid concomitant use. May potentially affect absorption of amiodarone, antiepileptics (e.g., valproate), levothyroxine (administer at least 4 hours apart), warfarin (monitor INR closely), and oral contraceptives (use additional contraception method). No significant interactions with alcohol, digoxin, phenytoin, oral hypoglycemics, or nifedipine.

Missed dose

If a dose is missed, resume with the next scheduled dose. Do not double the dose to make up for a missed administration. The medication should only be taken when a meal contains fat.

Overdose

No serious adverse events have been reported with single doses up to 800 mg. Cases of overdose may result in an increase in gastrointestinal adverse effects. Management should be symptomatic and supportive. Medical attention should be sought if concerning symptoms develop.

Storage

Store at room temperature (15-30°C or 59-86°F). Keep in original container with desiccant. Protect from moisture and light. Keep out of reach of children. Do not use after expiration date.

Disclaimer

This information is for educational purposes only and does not replace professional medical advice. Xenical is a prescription medication that should be used only under the supervision of a qualified healthcare provider. Individual results may vary. Patients should discuss their medical history and potential risks with their physician before beginning treatment.

Reviews

Clinical trials demonstrate that Xenical plus diet produces significantly greater weight loss than placebo plus diet. In one-year studies, 35.5% of orlistat-treated patients achieved ≥5% weight loss compared to 21% with placebo. Approximately 20% achieved ≥10% weight loss versus 11% with placebo. Long-term studies show maintained weight loss advantage at 2 years. Patient-reported outcomes indicate improvements in quality of life measures and satisfaction with treatment despite gastrointestinal side effects, particularly when dietary fat intake is moderated.