Aripiprazole (Abilify)

Pharmacokinetics of Aripiprazole

Absorption Peak plasma concentrations occurring within 3 to 5 hours. Oral bioavailability is 87%.
Distribution 4.9 L/kg (99% bound to serum
proteins, primarily albumin)
Metabolism Hepatic
Elimination Hepatic (minimal renal)
Half-life 75 to 94 hours (long half life!)

Aripiprazole: Cytochrome P450 Metabolism

Substrate of (Metabolized by) 2D6, 3A4
Induces -
Inhibits -

Dosing for Aripiprazole

Starting 2 mg PO qAM
Titration 2-5 mg increments every 2-3 weeks
Maximum 30 mg (though 20 mg is a typical dose)
Taper
  • Aripiprazole comes in oral and intramuscular formulations.
  • Abilify Maintena is an extended-release (also known as long-acting) injectable suspension available in 400 mg or 300 mg formulations, given once every 4 weeks.
  • Any drugs that are CYP 2D6 inhibitors (e.g. - bupropion) can increase aripiprazole levels, which can cause akathisia, nausea/vomiting, and insomnia.[1]
  • There does not appear to be a bleeding risk although there are other possible haematological side effects, i.e. leucopenia, neutropenia or thrombocytopenia (incidence; 0.1% to 1%). CBC should be monitored.
  • Urinary retention has been rarely reported.[2]
  • Since aripiprazole is a partial dopamine agonist it is possible that the increased dopaminergic activity may induce impulsivity (similar to what is seen in patients on dopamine agonists like L-dopa).
  • Rare but serious impulse-control problems, such as pathological gambling, compulsive eating, compulsive shopping, and compulsive sexual behavior have been reported in patients treated with aripiprazole.[3]