Approaches to developing new anxiolytics and antidepressants.

The empirical approach to new treatments for anxiety and depression has been to test series of compounds that resemble medications in current use until one is found with similar actions but with fewer side effects. With the explosion of knowledge in neurobiology, it is becoming possible to develop treatments aimed more precisely at specific links in the chain of mood dysregulation. Examples of this informed approach include agonists for limbic but not cortical benzodiazepine receptors; compounds to stabilize serotonergic and noradrenergic transmission; and drugs that act on intracellular signals, such as the calcium ion and cyclic AMP. This article reviews neurobiologically informed approaches to developing new medications for anxiety and depression and discusses some of the innovative treatments that are emerging from such a strategy.