ORLISTAT
(or'li-stat)
Xenical
Classifications: gastrointestinal agent; anorectant; nonsystemic lipase inhibitor
Prototype: Diethylpropion
Pregnancy Category: B

Availability

120 mg capsules

Actions

Nonsystemic inhibitor of gastrointestinal lipase. Reduces intestinal absorption of dietary fat by forming inactive enzymes with pancreatic and gastric lipase in the GI tract.

Therapeutic Effects

Indicated by weight loss/decreased body mass index (BMI). Reduces the intestinal absorption of dietary fat because at least 95% of orlistat is eliminated in the feces; reduces caloric intake in obese individuals.

Uses

Weight loss and weight maintenance in patients with BMI 30 kg/m2 or 27 kg/m2 in patients with other risk factors. Reduce risk for weight regain after prior weight loss.

Contraindications

Hypersensitivity to orlistat; malabsorption syndrome; cholestasis; gallbladder disease; hypothyroidism; organic causes of obesity; anorexia nervosa, bulimia nervosa; organic causes of obesity, lactation. Safety and efficacy in children <16 y are not established.

Cautious Use

Gastrointestinal diseases including frequent diarrhea; known dietary deficiencies in fat soluble vitamins (i.e., A, D, E); history of calcium oxalate nephrolithiasis or hyperoxaluria; older adults; pregnancy (category B).

Route & Dosage

Weight Loss
Adult/Adolescent: PO >16 y, 120 mg t.i.d. with each main meal containing fat

Administration

Oral

Adverse Effects (1%)

Body as a Whole: Fatigue. CNS: Headache, dizziness, anxiety. CV: Hypertension, stroke. GI: Oily spotting, flatus with discharge, fecal urgency, fatty/oily stool, oily evacuation, increased defecation, fecal incontinence, abdominal pain/discomfort, nausea, infectious diarrhea, rectal pain/discomfort, tooth disorder, gingival disorder, vomiting. Skin: Rash. Urogenital: Menstrual irregularity.

Interactions

Drug: Orlistat may increase absorption of pravastatin; may decrease absorption of fat soluble vitamins (A, D, E, K). Monitor PT/INR inpatients on chronic stable doses of warfarin.

Pharmacokinetics

Absorption: Minimal absorption. Metabolism: Metabolized in gastrointestinal wall. Elimination: Excreted in feces. Half-Life: 1–2 h.

Nursing Implications

Assessment & Drug Effects

Patient & Family Education


Common adverse effects in italic, life-threatening effects underlined; generic names in bold; classifications in SMALL CAPS; Canadian drug name; Prototype drug