Xenical, known generically as orlistat, stands as a prominent medication in the management of obesity. Classified as a lipase inhibitor, its therapeutic efficacy lies in its ability to interfere with the absorption of dietary fats, aiding in weight loss and weight maintenance efforts.

Mechanism of Action

Xenical exerts its effects by inhibiting pancreatic lipase, an enzyme crucial for the breakdown and absorption of dietary fats. By blocking this enzyme, Xenical reduces the hydrolysis of triglycerides into absorbable free fatty acids and monoglycerides. Consequently, the unabsorbed fats are excreted in the stool, leading to a decrease in calorie intake and facilitating weight loss.

Indications and Usage

Xenical finds widespread use in the management of obesity, particularly in individuals with a body mass index (BMI) exceeding 30 kg/m² or those with a BMI of 27 kg/m² or higher coupled with comorbidities like hypertension, diabetes, or dyslipidemia. It is an adjunct to a comprehensive weight loss program that includes dietary modifications, exercise, and behavioral interventions.

Dosage and Administration

The dosage of Xenical is typically standardized, with patients advised to take 120 mg orally three times a day with each main meal containing fat. It should be consumed either during the meal or within one hour of eating. Compliance with a reduced-calorie, low-fat diet is paramount to optimize Xenical’s efficacy.

Dosage Table

Condition	Dosage
Obesity (BMI > 30 kg/m²)	120 mg three times daily
Obesity with Comorbidities	120 mg three times daily
Adjuvant to Weight Loss Program	120 mg three times daily

Contraindications and Precautions

Xenical is contraindicated in individuals with chronic malabsorption syndrome, cholestasis, or known hypersensitivity to orlistat. Caution is warranted in patients with a history of thyroid disease, pancreatitis, or gallbladder disorders. Regular monitoring of liver function tests and vitamin levels is recommended during treatment.

Adverse Effects

Common adverse effects of Xenical include gastrointestinal symptoms such as oily spotting, flatulence, fecal urgency, and fatty or oily stools. These effects are often transient and can be managed through adherence to a low-fat diet. Rarely, severe hepatotoxicity or allergic reactions may occur and necessitate immediate medical attention.

Drug Interactions

Xenical may alter the efficacy of medications by impairing their absorption. Notably, Xenical can ameliorate the anticoagulant effects of warfarin, necessitating close monitoring of prothrombin time. Concomitant use with antiepileptic drugs may require adjustments due to possible changes in the frequency or severity of seizures. A prudent approach should be taken with medications that have a narrow therapeutic window. Oral antidiabetic medicines or insulin dosage may need to be adjusted due to the potential improvement in metabolic control in diabetes achieved with weight loss.

Use in Specific Populations

As it pertains to pregnant women, Xenical is classified under pregnancy category X, thus disqualifying its use as the risks posed to the fetus outweigh potential benefits. Nursing mothers should also avoid this medication since it is unknown whether or not Xenical’s active components are excreted in human milk. The efficacy and safety of Xenical in pediatric patients have not been established. For geriatric populations, as there are no distinct differences demonstrated in response compared to younger adults, but greater sensitivity cannot be ruled out.

Overdosage

In instances of overdosage, patients are expected to experience the amplified effects of the drug’s known adverse reactions. While there have been no reports of serious toxic effects from Xenical overconsumption, patients may require supportive therapy. If warranted, the removal of unabsorbed material through the induction of emesis or gastric lavage may be necessary. Monitoring and supportive treatment should continue until clinical parameters return to normal.

Storage and Handling

Xenical is supplied in dark-blue, hard-gelatin capsules inscribed with ‘XENICAL 120’. These capsules come packaged in bottles and blister packs. Proper storage of Xenical capsules is significant to maintain product integrity; they should be kept in a cool, dry place, away from direct sunlight and moisture, and stored at 25°C (77°F) with excursions permitted to 15–30°C (59–86°F). Keep the medication out of reach of children to prevent accidental ingestion.

Patient Counseling Information

It is imperative for healthcare professionals to convey an understanding of Xenical’s therapeutic regimen to patients. Emphasis should be placed on adhering to a nutritionally balanced, reduced-calorie diet with roughly 30% of calories from fat. Instruct patients to take Xenical exactly as prescribed, along with the meal or up to one hour afterward. Patients must be made aware of the importance of taking a multivitamin supplementation once daily, at least 2 hours before or after the intake of Xenical. Individuals should also be informed of the possibility of changes in bowel movements and advised to report any symptoms of toxicity such as jaundice, dark urine, or loss of appetite.