Medications
Intuniv – Guanfacine
Uses
Side Effects
Interactions
Precautions
Uses
How Intuniv (Guanfacine) works
INTUNIV® is a central alpha2A-adrenergic receptor agonist indicated for the treatment of Attention Deficit Hyperactivity Disorder (ADHD) as monotherapy and as adjunctive therapy to stimulant medications.
Side Effects
What are the side effects of Intuniv (Guanfacine)?
Most common adverse reactions (≥5% and at least twice placebo rate) in the monotherapy trials:
- somnolence
- fatigue
- nausea
- lethargy
- hypotension
Most common adverse reactions (≥5% and at least twice placebo rate) in the adjunctive trial:
- somnolence
- fatigue
- insomnia
- dizziness
- abdominal pain
Interactions
- Strong CYP3A4 inhibitors (e.g., ketoconazole): Coadministration increases guanfacine exposure. Guanfacine dose should be limited to no more than 2 mg/day. When discontinuing CYP3A4 inhibitors, guanfacine dose should be doubled based on patient tolerability. The maximum dose should not exceed 4 mg/day .
- Strong CYP3A4 inducers (e.g., rifampin): Coadministration decreases guanfacine exposure. Guanfacine dose may be titrated up to 8 mg/day. When discontinuing CYP3A4 inducers, guanfacine dose should be decreased by half in 1-2 weeks based on patient tolerability. The maximum dose should not exceed 4 mg/day.
Precautions
- Hypotension, bradycardia, and syncope: Use INTUNIV® with caution in patients at risk for hypotension, bradycardia, heart block, or syncope (e.g., those taking antihypertensives). Measure heart rate and blood pressure prior to initiation of therapy, following dose increases, and periodically while on therapy. Advise patients to avoid becoming dehydrated or overheated.
- Sedation and somnolence: Occur commonly with INTUNIV® . Consider the potential for additive sedative effects with CNS depressant drugs. Caution patients against operating heavy equipment or driving until they know how they respond to INTUNIV®.
