TO READ: Why Did I Have To Gain 80 Pounds on Antipsychotics?
Researchers may have solved the mystery of why so many people with bipolar, depression, schizophrenia and other illnesses who take certain antipsychotic medications tend to gain weight -- sometimes lots of it.

While these medications may effectively treat symptoms such as hallucinations and delusions, that's a high price to pay. (I know -- I gained 80 pounds in a few months on one of these meds. Fortunately it's almost all come off now that I'm on a newer one instead.) Many people gain to the point that they become at risk for life-threatening conditions such as heart disease and diabetes.

Scientists knew that the link between brain cells and appetite seems to be an enzyme known as AMPK. Now, in a recent study at Johns Hopkins University, when researchers gave the antipsychotic medication clozapine to mice, their AMPK activity quadrupled. When the scientists chemically suppressed the mice's appetites, the AMPK levels lowered. But what mediates such a connection?

It turns out that histamine -- the substance responsible much allergic misery, as well as a protein which aids communication between cells -- plays a key role in the interaction between AMPK and appetite. By blocking histamine's effects, clozapine no longer led to AMPK spikes.

The results are exciting: This discovery may allow scientists to develop both a new generation of antipsychotic drugs that doesn't cause weight gain, and safe weight-loss drugs.

For more info: Proceedings of the National Academy of Sciences, online edition, February, 2007.