Drug Guide

Generic Name

Brexpiprazole

Brand Names Rexulti

Classification

Therapeutic: Antipsychotic

Pharmacological: Serotonin-Dopamine Activity Modulator

FDA Approved Indications

Mechanism of Action

Brexpiprazole is a partial agonist at serotonin 5-HT1A and dopamine D2 receptors and an antagonist at serotonin 5-HT2A receptors. Its activity modulates neurotransmission, which helps in alleviating symptoms of schizophrenia and depression.

Dosage and Administration

Adult: For schizophrenia: 1 mg once daily, may be increased to 2-4 mg/day based on response. For adjunctive treatment of depression: 0.5-1 mg/day, may titrate up to 3 mg/day.

Pediatric: Not indicated for pediatric use.

Geriatric: Starting dose typically lower (e.g., 0.5 mg), with careful titration.

Renal Impairment: Use with caution; no specific dose adjustment established.

Hepatic Impairment: Use with caution; lower initial doses recommended.

Pharmacokinetics

Absorption: Well-absorbed orally with approximately 95% bioavailability.

Distribution: Highly protein-bound (~99%).

Metabolism: Extensively metabolized in the liver primarily via CYP3A4 and CYP2D6 enzymes.

Excretion: Eliminated mainly via feces (~73%) and urine (~23%).

Half Life: Approximately 91 hours (range 75-112 hours).

Contraindications

Precautions

Adverse Reactions - Common

Adverse Reactions - Serious

Drug-Drug Interactions

Drug-Food Interactions

N/A

Drug-Herb Interactions

N/A

Nursing Implications

Assessment: Monitor for improvements in psychotic symptoms, monitor metabolic parameters, assess for side effects.

Diagnoses:

  • Risk for weight gain related to metabolic side effects
  • Risk for extrapyramidal symptoms
  • Risk for falls due to orthostatic hypotension

Implementation: Administer once daily, preferably at the same time each day. Monitor metabolic parameters regularly.

Evaluation: Assess symptom control, weight, glucose levels, lipid profile, and side effects periodically.

Patient/Family Teaching

Special Considerations

Black Box Warnings:

Genetic Factors: Consider pharmacogenetic testing for CYP2D6 or CYP3A4 enzyme variants if inconsistency in response or side effects.

Lab Test Interference: May alter blood glucose, lipid levels, and weight.

Overdose Management

Signs/Symptoms: Drowsiness, sedation, agitation, tachycardia, hypotension, seizures.

Treatment: Supportive care, gastric lavage, activated charcoal. No specific antidote available.

Storage and Handling

Storage: Store at room temperature, 20°C to 25°C (68°F to 77°F), away from moisture and light.

Stability: Stable for at least 24 months when stored properly.

This guide is for educational purposes only and is not intended for clinical use.