Orlistat

INTRODUCTION

Indications

Obesity management (weight loss and maintenance) when used in conjunction with a reduced-calorie diet in patients with an initial BMI ≥30 kg/m² or ≥27 kg/m² in the presence of additional risk factors (diabetes, hypertension, hyperlipidemia). Reduces the risk of weight regain after prior loss. May delay onset of type 2 diabetes in prediabetic patients.

Action

Decreases the absorption of dietary fat by reversibly inhibiting enzymes (lipases), which are necessary for the breakdown and subsequent absorption of fat. Therapeutic Effects: Weight loss and maintenance in obese patients. Delayed onset of type 2 diabetes.

Adverse Reactions/Side Effects

With initial use; incidence decreases with prolonged use

GI: fecal urgency, flatus with discharge, increased defecation, oily evacuation, oily spotting, fecal incontinence.

PHYSICAL THERAPY IMPLICATIONS

Examination and Evaluation

• Periodically assess body weight and other anthropometric measures (body mass index, body composition). Document whether drug therapy is helping reduce body weight and decrease percentage of body fat.

Interventions

• Design and implement aerobic exercise and endurance training programs to help decrease obesity and maintain weight loss.

Patient/Client-Related Instruction

• Counsel patients about additional interventions to help control obesity and improve cardiovascular health, including dietary modification, regular exercise, moderation of alcohol consumption, and smoking cessation.

• Advise patient about the likelihood of GI problems, including increased bowel movements, flatulence, and possible incontinence. Instruct patient to report severe or prolonged GI problems.

Pharmacokinetics

Absorption: Minimal systemic absorption.

Distribution: Action is local, within the GI tract.

Protein Binding: Minimally absorbed drug is >99% bound to plasma proteins.

Metabolism and Excretion: Major route is fecal elimination of unabsorbed drug.

Half-life: 1–2 hr.

Contraindications/Precautions

Contraindicated in: Hypersensitivity; Chronic malabsorption syndrome or cholestasis; OB: Pregnancy or lactation.

Use Cautiously in: Pedi: Children <16 yr (safety not established).

Interactions

Drug-Drug: Reduces the absorption of some fat-soluble vitamins and beta-carotene.

Route/Dosage

PO (Adults and adolescents ≥16 yr): 60–120 mg tid with each meal containing fat.

Availability

Capsules: 120 mg, 60 mg OTC.