Atypical antipsychotics: matching receptor profile to individual patient's clinical profile.

Understanding common pharmacologic and clinical "class" actions associated with atypical antipsychotics certainly reveals how these agents are alike, but what about unique differences from one agent to another? Atypical antipsychotics are also a heterogeneous group of agents that have complex pharmacologic entities, acting upon multiple dopamine receptors (D2, D1, D3, and D4) and multiple serotonin receptors (5-HT2A, 5-HT2C, 5-HT1A, and 5-HT1D, among others). Atypical antipsychotics also interact with noradrenergic (alpha 1- and alpha 2-adrenergic receptor blockade), histaminergic (H1-receptor blockade), and cholinergic (muscarinic M1 blockade) neurotransmitter systems as well as with monoamine (D, 5-HT, and norepinephrine reuptake blockade) transporters. However, no two atypical antipsychotics possess the same portfolio of actions upon all of these additional neurotransmitter systems.