Rexulti

Generic name: brexpiprazole

Drug class: Atypical antipsychotics

Dosage form: Oral tablet (0.25 mg, 0.5 mg, 1 mg, 2 mg, 3 mg, 4 mg)

Root of administration: Oral

Dose: For major depressive disorder (MDD) in adults: 2 mg to 3 mg once daily as adjunctive therapy to antidepressants. For schizophrenia in adults and adolescents aged 13 years and older: 2 mg to 4 mg once daily. For agitation associated with dementia due to Alzheimer’s disease in adults: 0.5 mg once daily on days 1 to 7, increasing to 2 mg once daily by day 15.

Mechanism of action: Brexpiprazole is a serotonin-dopamine activity modulator (SDAM) that acts as a partial agonist at dopamine D2 and serotonin 5-HT1A receptors and as an antagonist at serotonin 5-HT2A receptors, helping to balance neurotransmitter activity in the brain.

Drug usage cases:

• Adjunctive treatment for major depressive disorder in adults
• Treatment of schizophrenia in adults and adolescents aged 13 years and older
• Treatment of agitation associated with dementia due to Alzheimer’s disease in adults

Drug contraindications:

• Hypersensitivity to brexpiprazole or any component of the formulation
• Concurrent use with strong CYP3A4 inhibitors (e.g., ketoconazole) or strong CYP3A4 inducers (e.g., rifampin)
• Concurrent use with strong CYP2D6 inhibitors (e.g., paroxetine) or strong CYP2D6 inducers (e.g., rifampin)

Side effects:

• Common: Weight gain, akathisia (restlessness), drowsiness, dizziness, nasopharyngitis, sleep disturbances
• Serious: Neuroleptic malignant syndrome (NMS), tardive dyskinesia, hyperglycemia, seizures, orthostatic hypotension, falls, low white blood cell count

Warnings:

• Increased mortality in elderly patients with dementia-related psychosis
• Increased risk of suicidal thoughts and behaviors in patients aged 24 years and younger
• Risk of NMS, a potentially fatal condition
• Risk of tardive dyskinesia, which may be irreversible
• Monitor for signs of hyperglycemia and diabetes
• Monitor for orthostatic hypotension and falls
• Monitor for low white blood cell count

Use during pregnancy or breastfeeding: Brexpiprazole should be used during pregnancy only if the potential benefit justifies the potential risk to the fetus. Neonates exposed to antipsychotic drugs during the third trimester of pregnancy are at risk for extrapyramidal and/or withdrawal symptoms following delivery. It is not known if brexpiprazole is excreted in human breast milk. A decision should be made whether to discontinue nursing or to discontinue the drug, taking into account the importance of the drug to the mother.