What makes some of us eat and eat and eat, although we know that we kill ourselves?

Everyone and anyone has the answer, it seems, but drugs are working for a cure.

This week, dieters, doctors and investors get their first comprehensive look at three new pharmaceutical perspective. Except that only a truly new - the other two are combinations of existing drugs.

The hope is that the new pills will deliver significant weight loss without the dangerous side effects best embodied by Phen-fen, the drug combination pulled the market in 1997 because of links to heart valve damage and pulmonary problems.

Two of the drugs submitted for FDA approval - Cont Qnexa and Rave - seems quite effective, but both have disturbing side effects. The third, Lorcaserin, is safer, but does not seem to cut the fat too.

Considered to be effective, the FDA says obesity drug, total body weight reduction by at least five percent after one year.

Qnexa showed the best weight loss results in clinical trials with patients lose between 13 and 15 percent of their body weight.

But the drug, a combination of amphetamine and an anticonvulsant, also had the highest rate of patient dropouts due to adverse events - particularly memory and concentration problems.

Cont Rave, a combination of an antidepressant and an antiepileptic drug, weight loss was between 5 and 10 percent. Nausea was the main side effect.

Lorcaserin's behind door number three. It is a brand new drug that works on serotonin, the substance in the brains associated with feelings of satiety and well-being, according to the maker. Patients in the trials company lost only five percent of their body weight. However, they reported the fewest side effects - an important factor in obtaining FDA approval.

With American obesity nearly 35 percent, expectations were high for the first new prescription drug therapies to occur in more than a decade.

The FDA is expected to review Vivus Inc. 'pill Qnexa post on Monday and will hold a public meeting Thursday to examine the data. Arena Pharmaceuticals Inc. 's lorcaserin is set for an FDA panel review in September, while orexigenic Therapeutics Inc.' s Cont Rave will be the subject of a panel in December.