Orlistat And It's Use In Weight Loss Treatment

Orlistat which is also known as tetrahydrolipstatin, is a drug designed to treat obesity. Its primary function is preventing the absorption of fats from the human diet, thereby reducing caloric intake. It is intended for use in conjunction with a physician supervised reduced calorie diet. The effectiveness of orlistat in promoting weight loss is definite, though modest.
Clinical trials suggest that people given orlistat in addition to lifestyle modifications, such as diet and exercise, lose about 2–3 kilograms (4.4–6.6 lb) more than those not taking the drug over the course of a year. Orlistat also modestly reduces blood pressure, and appears to prevent the onset of type 2 diabetes. In a large randomized controlled trial, orlistat was found to reduce the incidence of diabetes by nearly 40% in obese people.

How Does Orlisat Work

Orlistat works by inhibiting gastric and pancreatic lipases, the enzymes that break down triglycerides in the intestine. When lipase activity is blocked, triglycerides from the diet are not hydrolyzed into absorbable free fatty acids, and are excreted undigested instead. Only trace amounts of orlistat are absorbed systemically; the primary effect is local lipase inhibition within the GI tract after an oral dose.

Orlisat Dosage

The standard prescription dose of 120 mg three times daily before meals, orlistat prevents approximately 30% of dietary fat from being absorbed, and about 25% at the standard over-the-counter dose of 60 mg. Higher doses do not produce more potent effects.

Efficacy Of Orlisat in Weight Loss

The amount of weight loss achieved with orlistat varies. In one-year clinical trials, between 35.5% and 54.8% of subjects achieved a 5% or greater decrease in body mass, although not all of this mass was necessarily fat. Between 16.4% and 24.8% achieved at least a 10% decrease in body mass. After orlistat was stopped, a significant number of subjects regained weight-up to 35% of the weight they had lost.

Orlistat contraindications

* Malabsorption
* Hypersensitivity to orlistat
* Reduced gallbladder function (e.g. after cholecystectomy)
* Pregnancy and breastfeeding
* Use caution with: obstructed bile duct, impaired liver function, and pancreatic disease

Availability And Packaging

Orlistat is marketed as a prescription under the trade name Xenical by Roche in most countries, or over-the-counter as Alli by GlaxoSmithKline in the United States. Generic Xenical Capsules are also available in 120 mg capsules.
In the United States, the European Union, and Australia, orlistat is available for sale without a prescription. In Canada it is sold as orlistat 120 mg capsules . Generic orlistat is also available under the brands Olistat, Vyfat, Obelit, and Reeshape.

Side effects of Orlisat

Orlistat is known for its gastrointestinal side effects, which can include steatorrhea (oily, loose stools). These side effects decrease with time, and are the only significant adverse effects of the drug, which appears to be safe for long term use.

Precautions To Be Taken

Absorption of fat-soluble vitamins and other fat-soluble nutrients is inhibited by the use of orlistat. A multivitamin tablet containing vitamins A, D, E, K, and beta-carotene should be taken once a day, at bedtime, when using orlistat.

Orlisat Interactions

Orlistat may reduce plasma levels of ciclosporin (also known as "cyclosporin" or "cyclosporine", trade names Sandimmune, Gengraf, Neoral, etc.), an immunosuppressive drug frequently used to prevent transplant rejection; the two drugs should therefore not be administered concomitantly.
Orlistat can also impair absorption of the antiarrhythmic amiodarone.

Further Information

Manufacturers pamphlet: Xenical Information

Considerable portions of the text here is from http://en.wikipedia.org/wiki/Orlistat and is reproduced here under the Creative Commons Attribution-ShareAlike License