Ziprasidone

Indications

Ziprasidone is used for: Schizophrenia, Bipolar Disorder, Mania

Adult Dose

Oral Schizophrenia Adult: As ziprasidone HCl: Initially, 20 mg bid, increase if necessary at intervals of not <2 days up to 80 mg bid. Maintenance: 20 mg bid. Acute mixed or manic episodes in bipolar disorder Adult: As ziprasidone HCl: Initially, 40 mg bid, increased to 60 mg or 80 mg bid on the 2nd day. Adjust subsequent doses according to patient's response and tolerance level. Maintenance treatment of bipolar I disorder (adjunctive therapy to either lithium or valproate): Continue at the same dosage on which the patient was initially stabilised w/in 40-80 mg bid. Elderly: Lower initial dose and slower titration. Hepatic impairment: Use caution

Child Dose

Renal Dose

Renal impairment: Dose adjustment not necessary with PO administration;

Administration

Should be taken with food.

Contra Indications

Concomitant use of oral and IM ziprasidone. Recent acute MI, decompensated heart failure, cardiac arrhythmias, conditions that may increase QT interval eg, QT-interval prolongation or history of QT prolongation; prolactin dependent tumours. Lactation. Not for treatment of behavioural disorders in elderly with dementia.

Precautions

Patient w/ history of seizures or conditions that lower the seizure threshold, CV or cerebrovascular disease, conditions which predispose to hypotension. Renal impairment. Elderly w/ dementia-related psychosis. Pregnancy and lactation. Patient Counselling This drug may cause somnolence, impairment of judgment, thinking or motor skills, if affected, do not drive, operate machinery or perform hazardous tasks. Avoid alcohol. Monitoring Parameters Monitor serum electrolytes if on concurrent diuretic therapy. Monitor ECG in patients who show symptoms of torsades de pointes (e.g. syncope, dizziness, palpitations); wt gain. Closely monitor worsening of glucose control in patients w/ pre-existing DM. Frequently monitor CBC during 1st few mth of therapy in patients w/ pre-existing low leucocyte count or history of drug-induced leucopenia or neutropenia. Lactation: Unknown if excreted in breast milk; not recommended

Pregnancy-Lactation

Pregnancy category: C Neonates exposed to antipsychotic drugs during 3rd trimester of pregnancy are at risk for EPS or withdrawal symptoms after delivery; these complications vary in severity, with some being self-limited and others requiring ICU support and prolonged hospitalization Lactation: Unknown if excreted in breast milk; not recommended

Interactions

Antagonistic effect with levodopa and dopamine antagonists. Additive hypotensive effect with antihypertensives. Additive sedative effects with other CNS agents, alcohol. Potentially Fatal: Increased risk of torsades de pointes with drugs that prolong QT interval e.g. dofetilide, quinidine, sotalol, and other Class Ia and III antiarrhythmics, moxifloxacin, pimozide, sparfloxacin, thioridazine.

Adverse Effects

Side effects of Ziprasidone : >10% Somnolence (11-15%), Headache (11%), Nausea (4-12%), Extrapyramidal symptoms (2-31%), Dizziness (3-16%) 1-10% Respiratory disorders (1-8%), Constipation (2-9%), Dyspepsia (1-8%), Rash (4-5%), Tachycardia (2%), Hypoesthesia (2%), Priapism (1%), Orthostatic hypotension (5%), Xerostomia (1-5%), Anorexia (2%), Myalgia (2%), Rhinitis (1-4%), Cough (3%) <1% Syncope, Seizures Frequency Not Defined Prolongation of QT interval, Neuroleptic malignant syndrome (NMS), Hyperprolactinemia, Drug reaction with eosinophilia and systemic syntoms Potentially Fatal: Blood dyscrasias, neuroleptic malignant syndrome.

Mechanism of Action

Ziprasidone, an atypical antipsychotic, produces antischizophrenic effect through a combination of dopamine D2 and serotonin 5H2 receptor antagonism.