Ziprasidone — Geodon — has the most favorable metabolic profile among the effective SGAs. Minimal weight gain, minimal lipid effect, minimal glucose dysregulation. For patients where metabolic burden is the central concern, ziprasidone is a strong choice. Two practical features constrain its use: the food requirement and the QTc effect.
- Class
- Second-generation antipsychotic
- Mechanism
- D2 + 5-HT2A + 5-HT2C antagonism + 5-HT1A partial agonism + weak SERT/NET inhibition
- Typical dose
- Oral 40-160 mg/day in divided doses with food; IM 10-20 mg for acute agitation
- Half-life
- ~7 hours
- FDA indications
- Schizophrenia, bipolar I (acute mania, mixed episodes)
- Key adverse effects
- Sedation, dizziness, QTc prolongation (more than most SGAs), low weight gain, low metabolic effects, akathisia
Black box: Increased mortality in elderly patients with dementia-related psychosis
Food requirement is critical — absorption nearly doubles with food ≥500 kcal. Without food, subtherapeutic. QTc prolongation: ECG at baseline, screen for cardiac risk factors, caution with QTc-prolonging combinations. Favorable metabolic profile — useful when weight/metabolic concerns dominate.
Bioavailability of ziprasidone roughly doubles with food. The FDA label specifies a meal of at least 500 calories. Without food, plasma levels are markedly subtherapeutic — the patient who takes ziprasidone on an empty stomach is essentially undertreated. This is the single most important counseling point: take with a meal, not a snack, and the meal must be substantial. Patients who skip meals will have unreliable effect.
QTc prolongation is more prominent with ziprasidone than with most other SGAs. Baseline ECG before initiation. Drug interaction screening — avoid combinations with other QTc-prolonging agents (methadone, ondansetron, certain antibiotics, certain antiarrhythmics). Caution in patients with congenital long QT, hypokalemia, hypomagnesemia, or significant bradycardia. For the patient with cardiac risk factors, ziprasidone is often not the right choice.
The mechanism is D2 antagonism + 5-HT2A antagonism, plus 5-HT1A partial agonism and weak SERT/NET inhibition. The 5-HT1A activity may contribute to anxiolysis and may explain why ziprasidone is often less sedating than other SGAs. Akathisia is the more common acute side effect; some patients find it limiting.
Ziprasidone is a metabolically favorable SGA whose two clinical caveats — a food requirement and QTc prolongation — define its practical use.
Mechanism note: Ziprasidone's metabolic neutrality is its selling point; the food requirement and QTc concern are the two practical constraints that determine whether it is the right choice.
FDA approvals: schizophrenia, bipolar I (acute mania, mixed episodes). IM ziprasidone is available for acute agitation — onset within an hour, useful when the patient cannot tolerate IM haloperidol's EPS profile.
- Cost
- Generic: ~$30-100/month.
- Generic status
- Generic since 2012.
- Formulary typical
- Tier 1-2 generic.
- Access friction
- Food requirement is daily friction. IM available in EDs for acute agitation.
Prescriber tip: Counsel meal-with-medication explicitly. The patient who can't reliably eat substantial meals at consistent times will have unreliable absorption.
For the patient with metabolic risk who needs an effective SGA, ziprasidone is a strong contender — but only if the food adherence is reliable and the cardiac profile is clean.