Home Drug Guide Paliperidone Palmitate

Drug Guide

Generic Name

Paliperidone Palmitate

Brand Names Invega Sustenna, Invega Trinza, Invega Hafyera, Erzofri

Classification

Therapeutic: Antipsychotic, Schizophrenia treatment

Pharmacological: Atypical antipsychotic, long-acting injectable

FDA Approved Indications

Schizophrenia in adults

Mechanism of Action

Paliperidone is an antagonist at dopamine D2 and serotonin 5-HT2A receptors, which helps modulate neurotransmission and reduce psychotic symptoms.

Dosage and Administration

Adult: Initially, 234 mg on day 1 and 156 mg 7 days later, then maintenance doses of 39-234 mg once monthly for Invega Sustenna, every 3 months for Invega Trinza, and every 6 months for Invega Hafyera. Dose adjustments based on clinical response.

Pediatric: Not approved for pediatric use.

Geriatric: Use cautiously; adjust dosing as needed considering hepatic and renal function.

Renal Impairment: Use with caution; no dose adjustment necessary for mild to moderate impairment. Limited data available.

Hepatic Impairment: Use cautiously; no specific adjustment recommended.

Pharmacokinetics

Absorption: Long-acting injectable with sustained release.

Distribution: Extensively bound to plasma proteins (~74%).

Metabolism: Partially metabolized by CYP3A4 and CYP2D6.

Excretion: Primarily excreted in urine (approximately 59%), with the remainder in feces.

Half Life: Invega Hafyera: approximately 126 days (steady state after multiple doses). Invega Trinza: approximately 87 days.

Contraindications

Hypersensitivity to paliperidone or related compounds.

Precautions

History of cardiovascular disease, cerebrovascular disease, orthostatic hypotension, seizures, or conditions that could be exacerbated by dopamine blockade.
Use cautiously in elderly patients with dementia-related psychosis due to increased mortality risk.

Adverse Reactions - Common

Injection site pain (Common)
Weight gain (Common)
Akathisia (Common)
Somnolence (Common)

Adverse Reactions - Serious

Neuroleptic malignant syndrome (Rare)
QT prolongation leading to arrhythmias (Rare)
Orthostatic hypotension (Rare)

Drug-Drug Interactions

CNS depressants
Other QT prolonging agents, Antihypertensives, Drugs affecting CYP3A4

Drug-Food Interactions

N/A

Drug-Herb Interactions

N/A

Nursing Implications

Assessment: Monitor mental status, mood, and behavior. Check for signs of EPS or TD. Assess for orthostatic hypotension.

Diagnoses:

Risk for falls
Imbalanced nutrition: less than body requirements

Implementation: Administer deep IM injection; ensure patient is monitored post-injection for adverse effects. Educate patient on injection schedule.

Evaluation: Evaluate symptom control and monitor for adverse reactions.

Patient/Family Teaching

Do not stop medication abruptly.
Report any unusual movements, fever, or signs of infection.
Be aware of ingestion side effects like weight gain and drowsiness.
Attend scheduled injections and follow-up appointments.

Special Considerations

Black Box Warnings:

Increased mortality in elderly patients with dementia-related psychosis.

Genetic Factors: No specific genetic contraindications but monitor for individual adverse reactions.

Lab Test Interference: Potential for increased prolactin levels, which can affect menstrual cycles and bone density.

Overdose Management

Signs/Symptoms: Sedation, hypotension, extrapyramidal symptoms, seizures.

Treatment: Supportive care, activated charcoal if early, and symptomatic treatment. No specific antidote.

Storage and Handling

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

Stability: Stable for the duration specified on packaging when stored properly.