Ziprasidone: profile on safety

Ziprasidone (Geodon, Pfizer) is the latest of a new class of atypical antipsychotics, following the release of clozapine, risperidone, olanzapine and quetiapine. It has a serotonin Type 2a/dopamine Type 2 (5-HT2a/D2) receptor (R) binding ratio of approximately 8:1; amongst the highest of its class. Furthermore, it is a potent 5-HT1aR agonist, and displays 5-HT1dR and 5-HT2cR antagonist activity, with unique effects on blocking the re-uptake of both 5-HT and noradrenaline (NE). Finally, ziprasidone has low-to-modest affinity for histamine (H1) and alpha 1-adrenoceptors and a negligible affinity for muscarinic (M1) Rs. This combination of effects may be responsible for its low rate of general adverse events, low rate of persistent prolactin elevation, low incidence of weight gain, low liability for inducing movement disorders, low rate of syncope and induction of decreases in lipid profile. Data on the effect of ziprasidone on the electrocardiogram (ECG) indicates a relatively higher degree of change in measure of QTc but no cases of mortality from overdoses, torsade de pointes (TdP) or excess in sudden and unexpected deaths.