aripiprazole monohydrate

General information

• Class: Long-acting injectable antipsychotic
• Common US brands: ABILIFY MAINTENA
• Typical dose range: Initiation typically follows a “confirm oral tolerability” approach: establish an effective oral dose, administer the first injection, and continue a short oral overlap per label while depot concentrations rise.
• Long-acting injectable formulation available.
• Therapeutic drug monitoring not routinely recommended; reference range 120–270 ng/mL.
• Last reviewed: 2025-12-30

Dosing & forms

• Forms/strengths: Intramuscular injection (monthly): 300 mg, 400 mg (deltoid or gluteal).
• Frequency: Maintenance is usually once monthly; dose selection (e.g., 300 mg vs 400 mg) is individualized to response, tolerability, and interaction profile.
• Typical range: Initiation typically follows a “confirm oral tolerability” approach: establish an effective oral dose, administer the first injection, and continue a short oral overlap per label while depot concentrations rise.
• Therapeutic range: 120–270 ng/mL

Mechanism (brief)

Long-acting injectable aripiprazole formulation (D2/D3 partial agonist with 5-HT1A partial agonism and 5-HT2A antagonism) intended for maintenance treatment when monthly dosing supports adherence and relapse prevention.

Metabolism & Half‑life

• Metabolism: CYP2D6, CYP3A4
• Half‑life: Steady-state range 718–1116 h

Therapeutic Drug Monitoring (TDM)

Recommended: No

Reference range: 120–270 ng/mL

Long‑acting injectable (LAI)

Monitoring highlights

• Weight/BMI and waist circumference; fasting lipids and glucose/HbA1c at baseline and periodically.
• Movement disorder monitoring (akathisia, parkinsonism, tardive dyskinesia), especially after initiation.
• Blood pressure/orthostasis when clinically indicated (older adults, dehydration, antihypertensive co-use).
• Injection site assessment and documentation (deltoid vs gluteal, local reactions).

Sources

• ABILIFY MAINTENA (aripiprazole) extended-release injectable suspension — Prescribing Information — DailyMed (2025)
• Safety of once-monthly aripiprazole initiation in schizophrenia — Current Medical Research and Opinion (2013)
• The American Psychiatric Association Practice Guideline for the Treatment of Patients With Schizophrenia — American Psychiatric Association (2020)
• Consensus Guidelines for Therapeutic Drug Monitoring in Neuropsychopharmacology: Update 2017 — Pharmacopsychiatry (2018)