ziprasidoni

Ziprasidone, sometimes written ziprasidoni, is an atypical antipsychotic medication used to treat schizophrenia and bipolar I disorder. It is a second-generation antipsychotic that exerts its therapeutic effects mainly as an antagonist of dopamine D2 and serotonin 5-HT2A receptors. It has a high affinity for those targets and, unlike some other antipsychotics, tends to produce less weight gain and certain metabolic side effects, though individual responses vary. Ziprasidone also has modest activity on other receptors and may inhibit serotonin and norepinephrine reuptake to a small degree, which may contribute to symptomatic control.

The drug is available as oral capsules and as an intramuscular (IM) formulation for acute agitation in patients with schizophrenia or bipolar mania. When taken orally, ziprasidone should be taken with meals to maximize absorption; without food, bioavailability is reduced. Dosing commonly ranges from 20 mg to 80 mg twice daily, with adjustments for efficacy and tolerability; the IM form is used for rapid symptom control when patients cannot take oral medication.

Common adverse effects include somnolence, dizziness, nausea, constipation, and akathisia; extrapyramidal symptoms can occur, particularly at higher doses. Weight change and metabolic effects are generally modest compared with some other antipsychotics. A key safety concern is QT interval prolongation on the electrocardiogram, which can increase the risk of cardiac arrhythmias in susceptible individuals; risk is higher with electrolyte disturbances or use of other QT-prolonging drugs. Ziprasidone should be avoided or used with caution in patients with known QT prolongation, recent myocardial infarction, or congestive heart failure. It is generally categorized as pregnancy category C.

In terms of pharmacokinetics, ziprasidone is primarily metabolized in the liver, mainly by aldehyde oxidase, with minor contributions from cytochrome P450 enzymes. It is excreted in urine and feces.