Orlistat
Antiobesity Preparations · Lipase inhibitor
Indications
Adjunct to diet in obese patients with body mass index 30 kg/m2 and greater, or body mass index 28 kg/m2 and greater with associated risk factors.
Dosage
Adults: 120 mg before, during or up to one hr after each main meal. Discontinue treatment after 12 wk if 5% of initial body weight is not lost. Children: Not recommended.
Adverse Effects
Faecal incontinence, oily stools, GI upset, respiratory infection, influenza, headache, menstrual irregularity, anxiety, fatigue, UTI. Very rarely, raised liver enzymes, hepatitis, rectal bleeding. Hypoglycaemia and abdominal distension in patients with type II diabetes. Tooth and gingival disorders, hypothyroidism, rectal bleeding, oxalate nephropathy.
Risk Factor (Pregnancy/Lactation)
Pregnancy: No evidence of risk in humans. Lactation: Contraindicated or not recommended. Contraindications: Chronic malabsorption, cholestasis. Precautions: Advise diet rich in fruit and vegetables containing approx 30% calories from fat. Consider a multivitamin supplement. Monitor antidiabetic drug treatment as diabetic patients lose weight. Possible failure of oral contraception due to severe diarrhoea. Chronic kidney disease.
Interactions
Acarbose, anticoagulants, amiodarone, fat-soluble vitamins, cyclosporin, antidiabetic drugs, anticonvulsants, levothyroxine, iodine salts, oral contraceptives, antidepressants, antipsychotics, lithium, antiretrovirals, benzodiazepines.
Advice to Patient
Take with meals or immediately before meals or up to 1 hour after meals that contain fat. Contact prescriber if there is continuous back, muscle or joint pain; signs of respiratory tract infection or flu-like symptoms or skin rash or irritation. If a meal is missed or it contains no fat, the dose may be omitted. If prescribed, take a multivitamin that contains fat-soluble vitamins and beta-carotene at least 2 hours before or after medication. If levothyroxine is also prescribed, there should be a 4 hour gap between orlistat and levothyroxine. Exercise regularly. Reduce dietary fats to prevent GI adverse effects of orlistat.
Pharmacokinetics
Onset of action: 24-48 hrs. Duration: 48-72 hrs. Absorption: Minimal. Metabolism: Within the gastrointestinal wall. Half-life elimination: 1-2 hrs. Time to peak, serum: Approx. 8 hrs. Excretion: Faeces (Approx. 97%), urine (<2%).
Unlicensed Use
Children: Adjunct in obesity: 12-18 yr, 120 mg taken immediately before, during, or up to 1 hr after each main meal, max 120 mg 3 times daily; continue treatment beyond 12 wk only under specialist recommendation. If a meal is missed or contains no fat, the dose of orlistat should be omitted.
Brands with this active ingredient
Compiled by Healify Pharmacy from published drug references. How we compile it →
Always consult a pharmacist or doctor.