Ziprasidone

A to Z Drug Facts

 Action Antipsychotic activity, apparently because of dopamine and serotonin receptor antagonism.

 Indications Treatment of schizophrenia; treatment of acute agitation in schizophrenic patients (injection only).

 Contraindications Drugs known to prolong the QT interval (eg, quinidine, pimozide, sotalol); patients with a history of QT prolongation; recent acute MI; uncompensated heart failure.

 Route/Dosage

ADULTS: PO 20 to 80 mg bid. IM 10 to 20 mg/day (max, 40 mg/day).

 Interactions

Alcohol, CNS-acting drugs: May cause additive CNS effects.

Antihypertensive agents: Hypotensive effects may be enhanced.

Carbamazepine: May reduce ziprasidone levels, decreasing the effectiveness.

Dofetilide, moxifloxacin, pimozide, quinidine, sotalol, sparfloxacin, thioridazine, any other drug known to prolong the QT interval: Increased risk of torsades de pointes or other malignant ventricular arrhythmias.

Ketoconazole, other inhibitors of cytochrome P450 3A4 metabolism: May elevate ziprasidone levels, increasing the risk of toxicity.

Dopamine agonists, levodopa: Effects may be antagonized.

 Lab Test Interferences None well documented.

 Adverse Reactions

CV: Tachycardia; postural hypotension; QT interval prolongation; hypertension. CNS: Somnolence; akathisia; dizziness; extrapyramidal syndrome; dystonia; hypertonia; anxiety; tremor; agitation; dyskinesia; hostility; paresthesia; confusion; vertigo; hypokinesia; hyperkinesia; abnormal gait; hypesthesia; ataxia; amnesia; cogwheel rigidity; delerium; hypotonia; akinesia; dysarthria; withdrawal syndrome; choreoathetosis; incoordination; neuropathy. DERM: Rash; fungal dermatitis; photosensitivity. EENT: Dry mouth; rhinitis; abnormal vision; oculogyric crisis; buccoglossal syndrome; diplopia. GI: Nausea; constipation; dyspepsia; diarrhea; anorexia; increased salivation; abdominal pain; vomiting. META: Weight gain. RESP: Respiratory disorder; increased cough; dyspnea. OTHER: Asthenia; accidental injury; myalgia; arthralgia; flu-like syndrome; fever; facial edema; chills; flank pain; hypothermia.

 Precautions

Pregnancy: Category C. Lactation: Undetermined. Children: Safety and efficacy not established. Elderly: Use with caution. Cardiovascular effects: QT prolongation with increased risk of life-threatening cardiovascular events may occur. Orthostatic hypotension may occur. Electrolyte disturbances: Hypokalemia or hypomagnesemia may increase risk of QT prolongation and arrhythmia. Suicide: Inherent in psychotic illness; use with caution and dispense in small quantities. Tardive dyskinesia: A potentially irreversible syndrome of involuntary body and facial movements may occur.

 Administration/Storage

• Administer with meals.
• Have patient swallow whole. Do not crush, chew, or open capsules.
• Store at controlled room temperature.

 Assessment/Interventions

• Obtain patient history, including drug history, and any known allergies. Note history of liver disease, QT prolongation, recent MI, cardiac arrhythmias, CHF, previous episodes of neuroleptic malignant syndrome, or seizures.
• Determine baseline electrolytes before starting therapy in patients taking diuretics.
• Monitor cardiac patients during initiation of drug for prolongation of the QT interval and orthostatic hypotension; notify health care provider if either occurs.
• Inform health care provider immediately if hyperpyrexia, muscle rigidity, altered mental status, irregular pulse and BP, tachycardia, diaphoresis, palpitations, syncope, tachycardia, excessive drowsiness, nausea, constipation, or indigestion develop.
• Assess baseline neurologic status and observe for involuntary body and facial movements, drowsiness, agitation, anxiety, aggressive reaction, or seizure activity during treatment.
• Monitor patient for suicidal tendencies often associated with schizophrenia.
• Assess medication compliance.

 Patient/Family Education

• Explain name, dose, action, and potential side effects of drug.
• Advise patient not to crush or chew medication and to swallow capsules whole.
• Instruct patient to take each dose with food.
• Instruct patient to continue taking ziprasidone even if feeling better.
• Tell patient to immediately report fainting or loss of consciousness, palpitations, high fever, muscle rigidity, altered mental status, irregular pulse, sweating, seizures, or rash to health care provider.
• Advise patient to avoid strenuous activity during periods of high temperature or humidity.
• Instruct patient to avoid alcoholic beverages.
• Instruct patient to rise slowly from a lying or sitting position and to avoid sudden position changes to prevent postural hypotension. Advise patient to report dizziness with position changes to health care provider. Caution patient that hot tubs and hot showers or baths may worsen dizziness.
• Advise patient to take sips of water, suck on ice chips or sugarless hard candy, or chew sugarless gum if dry mouth occurs.
• Advise patient that drug may cause drowsiness and to use caution while driving or performing other tasks requiring mental alertness.
• Advise patient about potential weight gain.
• Instruct patient to notify health care provider if becoming pregnant, planning on becoming pregnant, or breastfeeding.
• Instruct patient to notify health care provider of any of the following symptoms: excessive drowsiness, increased agitation or anxiety, involuntary body or facial movements, rapid pulse, nausea, indigestion, constipation.
• Instruct patient to avoid taking any prescription or OTC medications or dietary supplements unless advised by the health care provider.

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Copyright © 2003 Facts and Comparisons
David S. Tatro
A to Z Drug Facts