What is the class of drug of Aripiprazole (Atypical Antipsychotic)?

From the Guidelines

Aripiprazole is a second-generation antipsychotic that is generally considered to have a lower risk of weight gain compared to other antipsychotics, making it a preferable option for patients with weight concerns. Aripiprazole works by acting as a partial agonist at dopamine D2 and serotonin 5-HT1A receptors, while also functioning as an antagonist at 5-HT2A receptors, which helps reduce the risk of certain side effects common to other antipsychotics 1.

Key Characteristics of Aripiprazole

• Aripiprazole is FDA-approved for treating schizophrenia, bipolar disorder, major depressive disorder (as an adjunct therapy), irritability associated with autism, and Tourette's syndrome.
• Typical dosing ranges from 2-30 mg daily depending on the condition being treated, with most adults starting at 10-15 mg daily.
• The medication is available in oral tablets, orally disintegrating tablets, oral solution, and long-acting injectable formulations.
• Common side effects include akathisia (restlessness), headache, insomnia, and weight gain, though the metabolic side effects tend to be less severe than with other atypical antipsychotics.

Comparison with Other Antipsychotics

• Aripiprazole, along with lurasidone and ziprasidone, appears to be more weight-neutral compared to other antipsychotics like olanzapine, clozapine, quetiapine, and risperidone, which are consistently associated with weight gain 1.
• The unique mechanism of action of aripiprazole contributes to its favorable side effect profile, making it a valuable option for patients who are at risk of weight gain or metabolic disturbances.

Clinical Considerations

• Regular monitoring of metabolic parameters is still recommended during treatment with aripiprazole, despite its more favorable metabolic profile compared to other antipsychotics.
• The choice of antipsychotic should be guided by the individual patient's circumstances, including their medical history, current health status, and specific treatment needs.
• Aripiprazole's dosing and administration should be tailored to the patient's response and tolerance, with adjustments made as necessary to minimize side effects and optimize therapeutic outcomes 1.

From the Research

Aripiprazole Class of Drug

• Aripiprazole is an atypical antipsychotic drug indicated for the treatment of adult patients with schizophrenia 2.
• It is a quinolinone derivative with a high affinity for dopamine D2 and D3 receptors, and serotonin 5-HT1A, 5-HT2A, and 5-HT2B receptors 2.
• The mechanism of action of aripiprazole is not yet known, but evidence suggests that its efficacy in the treatment of the positive and negative symptoms of schizophrenia and its lower propensity for extrapyramidal symptoms (EPS) may be attributable to aripiprazole's partial agonist activity at dopamine D2 receptors 2.

Pharmacological Properties

• Aripiprazole is rapidly absorbed after oral administration, with a mean time to peak plasma concentration of 3 hours following multiple-dose administration of aripiprazole 10 or 15 mg 2.
• The absolute oral bioavailability of the drug is 87%, and steady-state plasma drug concentrations are achieved by 14 days 2.
• Aripiprazole has extensive extravascular distribution, and more than 99% of aripiprazole and dehydro-aripiprazole (the main active metabolite of aripiprazole) is bound to plasma protein 2.

Therapeutic Efficacy

• The efficacy of aripiprazole has been demonstrated in patients with schizophrenia or schizoaffective disorder, with significant reductions from baseline in mean Positive and Negative Syndrome Scale total, positive and negative symptom scores, and Clinical Global Impression Severity of Illness scores 2.
• Aripiprazole is effective as early as the first or second week of treatment, and its efficacy is maintained for up to 52 weeks 2.
• Aripiprazole may improve cognitive function, with patients with chronic schizophrenia receiving aripiprazole 30 mg/day experiencing similar or better changes from baseline in neurocognitive parameters compared with recipients of olanzapine 10-15 mg/day 2.

Tolerability and Safety

• Aripiprazole is generally well tolerated, with a tolerability profile broadly similar to that observed with placebo in short-term trials in patients with acute relapse of schizophrenia or schizoaffective disorder 2.
• The most frequent treatment-emergent adverse events included insomnia and anxiety, and additionally, headache and agitation (in short-term trials) or akathisia and psychosis (in a 52-week trial) 2.
• Aripiprazole has a low propensity to cause clinically significant bodyweight gain, hyperprolactinaemia, or corrected QT interval prolongation in patients with schizophrenia or schizoaffective disorder 2, 3, 4.