I just read some papers in the British Medical Journal on the new prescription anti-obesity drugs, alli/orlistat being one of them.
A few of the interesting and relevant bits
0.4 millijoules (100 kcals) is the average energy expended per day by taking Alli over the counter, equivalent to 10-20 min of sex
-the drug does appear to be safe, but there are fat soluble vitamins which may become deficient with chronic use
-the main side effects are steatorrhoea, or fat in your stools, and faecal incontinence, which basically means losing it in your pants
-while the clinical trials have shown people to lose 10% of thier initial weight, this was because particpants in motivated and highly supported by staff who reinforce lifestyle advice
-the benefit of alli over a placebo in the clinical trials is small, typically 2.5 kg/6 pounds after one year
-in clinical trials 40% of the people dropped out of the anti-obesity studies
-to date, the sales of the drug have been 155 million dollars
-alli is ranked 57th out of 200 by the Consumer Price-Watch, whose top 10 pills are known to be dangerous or devoid of evidence that they actually work (or both)
The BMJ concludes the only beneficiaries of this drug is Glaxo Kline Smith
Also, if you want to put on muscle, your body needs nutrients to grow muscle, and that includes proteins, carbohydrates, fat and the fat soluble vitamins.
There is no substitute for a healthy diet and lifestyle.