Formulary
Orlistat: Indications, Dosing, Side Effects and Interactions
Orlistat, a lipase inhibitor, reduces the absorption of dietary fat.
MedNext Academy | 3 min read
Orlistat: Indications, Dosing, Side Effects and Interactions
Orlistat, a lipase inhibitor, reduces the absorption of dietary fat.
Drug action
Orlistat, a lipase inhibitor, reduces the absorption of dietary fat.
Indications and dose
**Adjunct in obesity (in conjunction with a mildly hypocaloric diet in individuals with a body mass index (BMI) of 30 kg/m2or more or in individuals with a BMI of 28 kg/m2or more in the presence of other risk factors such as type 2 diabetes, hypertension, or hypercholesterolaemia)**
- **Adult** (By Mouth): Adjunct in obesity (in conjunction with a mildly hypocaloric diet in individuals with a body mass index (BMI) of 30 kg/m 2 or more or in individuals with a BMI of 28 kg/m 2 or more in the presence of other risk factors such as type 2 diabetes, hypertension, or hypercholesterolaemia) 120 mg up to 3 times a day, dose to be taken immediately before, during, or up to 1 hour after each main meal, continue treatment beyond 12 weeks only if weight loss since start of treatment exceeds 5% (target for initial weight loss may be lower in patients with type 2 diabetes), if a meal is missed or contains no fat, the dose of orlistat should be omitted.
**Adjunct in obesity for orlistat**
- **Child 12-17 years (initiated by a specialist)** (By mouth): 120 mg up to 3 times a day, dose to be taken immediately before, during, or up to 1 hour after each main meal, continue treatment beyond 12 weeks only under specialist supervision, if a meal is missed or contains no fat, the dose of orlistat should be omitted.
Cautions
Chronic kidney disease; may impair absorption of fat-soluble vitamins; volume depletion Cautions, further information Vitamin supplementation (especially of vitamin D) may be considered if there is concern about deficiency of fat-soluble vitamins.
Contraindications
Cholestasis; chronic malabsorption syndrome
Side effects
Common or very common Abdominal pain (may be minimised by reduced fat intake); anxiety; diarrhoea; gastrointestinal disorders Frequency not known Anorectal haemorrhage; bullous dermatitis; cholelithiasis; diverticulitis; hepatitis; oxalate nephropathy; pancreatitis; renal failure
Interactions
**Other interactions (18):**
- Ciclosporin A decrease in ciclosporin plasma levels has been observed in a drug-drug interaction study and also reported in several cases, when orlistat was administered concomitantly.
- Oral anticoagulants When warfarin or other oral anticoagulants are given in combination with orlistat, international normalised ratio (INR) values could be affected (see section 4.8).
- Oral contraceptives The absence of an interaction between oral contraceptives and orlistat has been demonstrated in specific drug-drug interaction studies.
- However, orlistat may indirectly reduce the availability of oral contraceptives and lead to unexpected pregnancies in some individual cases.
- Levothyroxine Hypothyroidism and/or reduced control of hypothyroidism may occur when orlistat and levothyroxine are taken at the same time (see section 4.4).
- This could be due to a decreased absorption of iodine salts and/or levothyroxine.
Pregnancy
Use with caution.
Breast feeding
Avoid-no information available.
Medicinal forms
Clinical governance
**Author:** MedNext Clinical Team. **Clinical reviewer:** Dr Shameer Deen, MBBS, MS, MRCS. **Sources:** BNF, Indian Pharmacopoeia, CIMS India. **Correction:** Report errors at support@mednext.academy.
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