Home Drug Guide Ziprasidone Hydrochloride

Drug Guide

Generic Name

Ziprasidone Hydrochloride

Brand Names Geodon

Classification

Therapeutic: Antipsychotic, atypical

Pharmacological: Dopamine and serotonin receptor antagonist

FDA Approved Indications

Schizophrenia
Bipolar disorder (acute manic or mixed episodes)

Mechanism of Action

Ziprasidone works by antagonizing dopamine D2 receptors and serotonin 5-HT2A receptors, which helps modulate neurotransmission related to psychosis and mood disorders.

Dosage and Administration

Adult: The usual starting dose for schizophrenia is 40 mg twice daily, titrated based on response. For bipolar disorder, 20 mg twice daily is common. Dose adjustments depend on clinical response and tolerability.

Pediatric: Not FDA approved for pediatric use; consult current guidelines for off-label use.

Geriatric: Start at lower doses due to increased sensitivity; monitor closely.

Renal Impairment: Use with caution; dose adjustments may be necessary based on renal function.

Hepatic Impairment: Use caution; consider lower doses due to hepatic metabolism.

Pharmacokinetics

Absorption: Well absorbed after oral administration.

Distribution: Widely distributed, crosses the blood-brain barrier.

Metabolism: Primarily metabolized in the liver via aldehyde oxidase and CYP3A4.

Excretion: Excreted mainly via urine and feces.

Half Life: Approximately 6 hours.

Contraindications

History of hypersensitivity to ziprasidone or other phenothiazines.
Concomitant use of drugs that prolong QT interval.

Precautions

Monitor ECG in patients with cardiovascular disease, electrolyte abnormalities, or those taking other medications that prolong QT interval. Use with caution in patients with epilepsy or a history of seizures.
Pregnancy category C; weigh benefits and risks during pregnancy. Breastfeeding is not recommended during treatment.

Adverse Reactions - Common

Dizziness (Common)
Somnolence (Common)
Nausea (Common)
Restlessness (Uncommon)

Adverse Reactions - Serious

QT prolongation leading to arrhythmias (e.g., Torsades de Pointes) (Rare)
Neuroleptic Malignant Syndrome (NMS) (Rare)
Extrapyramidal symptoms (Uncommon)

Drug-Drug Interactions

Medications prolonging QT interval (e.g., certain antiarrhythmics, antibiotics, other antipsychotics)

Drug-Food Interactions

N/A

Drug-Herb Interactions

N/A

Nursing Implications

Assessment: Monitor cardiac status (ECG), vital signs, and mental status. Assess for EPS and tardive dyskinesia.

Diagnoses:

Risk for QT prolongation
Risk for neuroleptic malignant syndrome

Implementation: Administer with food to improve absorption. Monitor for adverse effects and response.

Evaluation: Assess symptom control and side effects regularly.

Patient/Family Teaching

Advise patients to report signs of irregular heartbeat, dizziness, or fainting.
Warn about the risk of drowsiness and driving impairment.
Avoid alcohol and medications that can prolong QT interval without consulting a healthcare provider.

Special Considerations

Black Box Warnings:

QT prolongation and sudden death

Genetic Factors: Consider pharmacogenetic testing if recurrent side effects occur.

Lab Test Interference: May alter serum glucose, lipid levels, and ECG results.

Overdose Management

Signs/Symptoms: Dizziness, somnolence, and QT prolongation; seizures, coma in severe cases.

Treatment: Supportive care, continuous ECG monitoring, activated charcoal if ingestion is recent, and management of cardiac arrhythmias.

Storage and Handling

Storage: Store at room temperature, 20°C to 25°C (68°F to 77°F).

Stability: Stable under recommended storage conditions.