paliperidone

paliperidone,

an antipsychotic.

indication This drug is used to treat schizophrenia.

contraindications Lactation, seizure disorders, AV block, QT prolongation, torsade de pointes, and known hypersensitivity to this drug or to risperidone prohibit its use. Geriatric patients should not use this drug.

adverse effects Adverse effects of this drug include dizziness, orthostatic hypotension, blurred vision, vomiting, and weight gain. Life-threatening side effects include seizures, neuroleptic malignant syndrome, tachycardia, heart failure, and QT prolongation. Common side effects include EPS, pseudoparkinsonism, akathisia, dystonia, tardive dyskinesia, drowsiness, insomnia, agitation, anxiety, headache, nausea, anorexia, and constipation.

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paliperidone

Invega

Pharmacologic class: Benzisoxazole derivative

Therapeutic class: Antipsychotic

Pregnancy risk category C

FDA Boxed Warning

• Elderly patients with dementia-related psychosis are at increased risk for death. Over course of 10-week controlled trial, death rate in drug-treated patients was about 4.5%, compared to about 2.6% in placebo group. Although causes of death varied, most appeared to be cardiovascular or infectious. Don't give drug to patients with dementia-related psychosis.

Action

Unknown. In schizophrenia, therapeutic activity may be mediated through combination of central serotonin₂- and dopamine₂-receptor antagonism. Drug is a major active metabolite of risperidone.

Availability

Tablets (extended-release): 3 mg, 6 mg, 9 mg

⊘Indications and dosages

➣ Acute and maintenance treatment of schizophrenia

Adults: 6 mg P.O. once daily. Some patients may benefit from daily dosages as high as 12 mg or as low as 3 mg. If indicated, increase in increments of 3 mg/day at intervals of more than 5 days.

Dosage adjustment

• Renal impairment

Contraindications

• Hypersensitivity to drug, its components, or risperidone

Precautions

Use cautiously in:
• GI strictures (use should be avoided), cardiovascular or cerebrovascular disease, diabetes mellitus, Parkinson's disease, or conditions that raise body temperature (such as exercise, exposure to extreme heat, and concomitant anticholinergics use)
• increased risk of hypotension (as from dehydration, hypovolemia, or antihypertensives), aspiration pneumonia, or suicide attempt
• concurrent use of other drugs that are centrally acting or prolong the QT interval (use should be avoided)
• history of seizures or breast cancer
• elderly patients with dementia-related psychosis
• pregnant or breastfeeding patients
• children younger than age 18 (safety and efficacy not established).

Administration

• Give in morning with or without food.
• Administer tablets whole. Ensure that patient doesn't chew, divide, or crush them.

Route	Onset	Peak	Duration
P.O.	Unknown	24 hr	Unknown

Adverse reactions

CNS: dizziness, headache, akathisia, tardive dyskinesia, dystonia, extrapyramidal disorder, hypertonia, parkinsonism, sedation, somnolence, tremor, anxiety, asthenia, fatigue, seizure, stroke (in elderly patients with dementia-related psychosis), neuroleptic malignant syndrome (NMS)

CV: first-degree atrioventricular block, bundle-branch block, sinus arrhythmia, tachycardia, hypertension, orthostatic hypotension, prolonged QT interval, abnormal T wave, palpitations

EENT: blurred vision

GI: upper abdominal pain, dyspepsia, nausea, antiemetic effect, esophageal dysmotility, salivary hypersecretion, dry mouth

GU: hyperprolactinemia

Musculoskeletal: back pain, extremity pain

Respiratory: cough, dyspnea, aspiration pneumonia

Other: fever, weight gain, possible drug tolerance or dependency

Interactions

Drug-drug. Antihypertensives: increased risk of hypotension

Centrally acting drugs with sedative effect: increased sedation

Class IA antiarrhythmics (such as procainamide, quinidine), Class III antiarrhythmics (such as amiodarone, sotalol), anti-infectives (such as gatifloxacin, moxifloxacin), other antipsychotics (such as chlorpromazine, thioridazine), other drugs that prolong the QT interval: increased risk of prolonged QT interval

Dopamine agonists (such as levodopa): antagonized effects of these drugs

Drug-diagnostic tests. Blood glucose, serum prolactin: increased levels

Drug-food. Any food: possibly increased paliperidone effects

Drug-behaviors. Alcohol use: increased sedation

Patient monitoring

• Closely monitor patient at risk for suicide attempts.
• Monitor patient with diabetes regularly for signs and symptoms of worsening glycemic control.
• Stay alert for orthostatic hypotension.
☞ Monitor patient for signs and symptoms of NMS (extremely high fever, muscle rigidity, altered mental status, irregular pulse or blood pressure, tachycardia, diaphoresis, arrhythmias).
• Watch for signs and symptoms of drug tolerance, dependency, and abuse.

Patient teaching

• Inform patient he may take drug with or without food.
• Teach patient to take tablets whole and not to chew, divide, or crush them.
• Inform patient that tablet shell doesn't dissolve and may look like a complete tablet in stool.
☞ Instruct patient to immediately report signs or symptoms of NMS (such as high fever, muscle rigidity, altered mental status, irregular pulse or blood pressure, fast heart rate, or excessive sweating).
• Tell patient drug may cause temporary blood pressure decrease if he stands or sits up suddenly. Instruct him to rise slowly and carefully.
• Advise patient to take precautions against dehydration and overheating.
• Caution patient not to consume alcohol during therapy.
• Caution patient to avoid hazardous activities until drug's effects on concentration, coordination, vision, and alertness are known.
• As appropriate, review all other significant and life-threatening adverse reactions and interactions, especially those related to the drugs, tests, foods, and behaviors mentioned above.