What is the appropriate starting dose and titration schedule for Abilify (aripiprazole) in an adult patient, and how should the dose be adjusted for elderly individuals or those with hepatic impairment?

Abilify Maintena Starting Dose and Titration

Note: The user question asks about "Abilify Maintena" (the long-acting injectable formulation), but the provided evidence exclusively addresses oral aripiprazole. I will answer based on the available evidence for oral aripiprazole initiation and dosing.

Standard Adult Dosing

The recommended starting and target dose for oral aripiprazole is 10 or 15 mg once daily, administered without regard to meals, with no titration required. 1

• Aripiprazole has been systematically evaluated and proven effective in the dose range of 10 to 30 mg/day 1
• Doses higher than 10 or 15 mg/day were not more effective than the standard doses 1, 2
• Dosage increases should generally not be made before 2 weeks, the time needed to achieve steady-state plasma concentrations 1
• The drug demonstrates efficacy as early as the first or second week of treatment 2

Elderly Patients

Elderly or frail individuals should begin aripiprazole at 5 mg once daily and increase gradually as tolerated. 3

• This lower starting dose targets patients with increased sensitivity to medication effects 3
• No formal dosage adjustment is mandated by the FDA label for elderly patients, though caution is advised 1
• The drug has a long elimination half-life of approximately 75 hours, leading to 4-fold accumulation by day 14, which is particularly relevant in elderly patients 2

Hepatic Impairment

No dosage adjustment for aripiprazole is required based on hepatic function, even in severe hepatic impairment (Child-Pugh score between 5 and 15). 1

• This applies across the full spectrum of mild to severe hepatic impairment 1
• Similarly, no adjustment is needed for renal impairment (glomerular filtration rate between 15 and 90 mL/minute) 1

CYP2D6 Poor Metabolizers

Patients identified as poor metabolizers of CYP2D6 require an initial dose reduction to 5 mg to avoid excessive drug exposure. 3

• Approximately 8% of Caucasians and 3-8% of Black/African Americans are CYP2D6 poor metabolizers 1
• Dosage adjustments are mandatory when coadministered with CYP3A4 or CYP2D6 inhibitors (reduce dose) or strong CYP3A4 inducers (increase dose) 1

Early Adverse Effect Management

Clinicians should routinely monitor for early side effects such as headache, agitation, anxiety, insomnia, and akathisia during the first two weeks of therapy. 3

• If intolerable adverse effects arise within the first week, a temporary reduction to 5 mg is advised while assessing tolerability 3
• Administering aripiprazole at bedtime may lessen early insomnia or agitation by aligning any sedative effect with the sleep period 3
• The most frequent treatment-emergent adverse events include insomnia, anxiety, headache, and agitation 2
• Aripiprazole is associated with a placebo-level incidence of extrapyramidal symptoms and has a low propensity for weight gain, hyperprolactinemia, or QT prolongation 2

Adolescent Dosing (Ages 13-17)

The recommended target dose for adolescents is 10 mg/day, starting at 2 mg daily, titrated to 5 mg after 2 days, then to 10 mg after 2 additional days. 1

• Subsequent dose increases should be administered in 5 mg increments 1
• The 30 mg/day dose was not shown to be more efficacious than 10 mg/day in adolescents 1

Common Pitfalls to Avoid

• Do not titrate too rapidly: Wait at least 2 weeks before increasing doses to allow steady-state to be achieved 1
• Do not exceed 15 mg/day without clear rationale: Higher doses (20-30 mg/day) provide no additional therapeutic benefit in most patients 1, 2
• Do not overlook drug interactions: Review medications for CYP3A4 inducers (rifampin, phenobarbital, carbamazepine, phenytoin) or CYP2D6/3A4 inhibitors that require dose adjustments 1