ORLISTAT (XENICAL, ALLI)

Drug name: Orlistat

Brand names: Xenical, Alli

Use: Obesity management, weight loss

Orlistat is a lipase inhibitor that reduces the absorption of dietary fat -- about 30% of the fat intake from meals passes through the gut undigested.

Orlistat can help reduce weight (or maintain a lower body weight) by reducing the absorption of fat from the bowel, not by suppressing your appetite.

Xenical is licensed for sale over-the-counter in the USA & on prescription in the UK.

Alli is half the strength of xenical & may soon be available over-the-counter in the UK.

Over-the-counter anti-obesity drugs work best when combined with a reduced calorie, low-fat diet and regular exercise. When taking orlistat, each meal should contain no more than 15g of fat.

Contraindications:

- chronic malabsorption syndrome
- cholestasis
- pregnancy and breastfeeding

Side effects:

- flatulence (gas)
- increased urgency to open the bowels
- oily discharge or fatty stools
- abdominal distension (bloating) and pain
- faecal incontinence

Orlistat acts only in the gut, but it potentially inhibits the absorption of the fat-soluble vitamins A, D, E & K. Longer term this could carry risks of vitamin deficiency -- the manufacturer GlaxoSmithKline advises taking a daily multi-vitamin pill to protect against this.

Dose:

120mg at mealtime (max 3 doses per day).

If a meal is missed or contains no fat, the dose of orlistat should be omitted.