What is the starting dose of Abilify (aripiprazole) when used as an adjunct to Viibryd (vilazodone)?

Starting Dose of Aripiprazole as an Adjunct to Vilazodone (Viibryd)

The recommended starting dose of aripiprazole when used as an adjunct to vilazodone (Viibryd) is 2-5 mg once daily, with careful titration based on clinical response and tolerability. 1

Dosing Recommendations

• The FDA-approved starting dose for aripiprazole is 10-15 mg/day for schizophrenia, but when used as an adjunctive treatment, a lower starting dose is appropriate to minimize side effects 1
• For adjunctive therapy in depression, starting at a lower dose (2-5 mg daily) allows for assessment of tolerability before increasing the dose 2
• Titration should be gradual, with dose increases generally not made before 2 weeks, which is the time needed to achieve steady-state 1
• The target dose range for aripiprazole as an adjunctive treatment is typically 5-15 mg/day, though some patients may require up to 20 mg/day 2

Special Considerations

• For patients who are known CYP2D6 poor metabolizers, the dose should be reduced by half 1
• If the patient is taking strong CYP3A4 inhibitors (such as ketoconazole) or CYP2D6 inhibitors (such as fluoxetine or paroxetine), the aripiprazole dose should be reduced by half 1
• If both strong CYP2D6 and CYP3A4 inhibitors are used concurrently, the aripiprazole dose should be reduced to one-quarter of the usual dose 1

Monitoring and Titration

• Monitor for side effects including nausea, vomiting, insomnia, and akathisia 2
• Cardiovascular monitoring is important, particularly in patients with pre-existing cardiac conditions, as aripiprazole has been associated with cardiac effects in vulnerable individuals 3
• Rapid titration should be avoided, especially in elderly patients or those with comorbid medical conditions 3
• Efficacy assessment should be conducted after 4-6 weeks of treatment at a stable dose 2

Drug Interaction Considerations

• Vilazodone is a selective serotonin reuptake inhibitor (SSRI) with 5-HT1A receptor partial agonist activity 4, 5
• When combining aripiprazole with vilazodone, monitor for potential serotonergic effects due to their overlapping mechanisms 4
• The recommended therapeutic dose of vilazodone is 40 mg daily, and this should be maintained when adding aripiprazole 4
• Aripiprazole has shown efficacy as an augmentation agent for SSRIs in treatment-resistant depression 2

Efficacy and Safety

• In studies of aripiprazole augmentation for depression, doses between 2-15 mg/day have shown efficacy 2
• Lower doses (2-5 mg) may be effective for anxiety symptoms, while higher doses (10-15 mg) may be needed for depressive symptoms 2
• The safety profile of aripiprazole is generally favorable, but side effects can include akathisia, insomnia, and weight gain 6
• Studies have shown that 59% of patients with depression and anxiety disorders who had incomplete responses to SSRIs showed significant improvement with aripiprazole augmentation 2

Remember that while these are evidence-based recommendations, clinical response and individual patient factors should guide dose adjustments after initiating therapy at the recommended starting dose.