Guanfacine XR | Intuniv
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 (1).
- Recommended dose: 1 to 4 mg once daily in the morning or evening (2.2).
- Begin at a dose of 1 mg once daily and adjust in increments of no more than 1 mg/week (2.2).
- Do not crush, chew or break tablets before swallowing (2.1).
- Do not administer with high-fat meals, because of increased exposure (2.1).
- Do not substitute for immediate-release guanfacine tablets on a mg-per-mg basis, because of differing pharmacokinetic profiles (2.3).
- If switching from immediate-release guanfacine, discontinue that treatment and titrate with INTUNIV® as directed (2.3).
- Consider dosing on a mg/kg basis. Improvements observed starting at doses of 0.05-0.08 mg/kg once daily. Doses up to 0.12 mg/kg once daily may provide additional benefit (2.2).
- When discontinuing, taper the dose in decrements of no more than 1 mg every 3 to 7 days (2.5).
—–INDICATIONS AND USAGE—–
- See description above.
—–DOSAGE AND ADMINISTRATION—–
- See description above.
—–CONTRAINDICATIONS—–
- History of hypersensitivity to INTUNIV® , its inactive ingredients, or other products containing guanfacine (4).
—–WARNINGS & 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 (5.1).
- 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® (5.2).
—–ADVERSE REACTIONS—–
- Most common adverse reactions (≥5% and at least twice placebo rate) in the monotherapy trials: somnolence, fatigue, nausea, lethargy, and hypotension (6). Most common adverse reactions (≥5% and at least twice placebo rate) in the adjunctive trial: somnolence, fatigue, insomnia, dizziness, and abdominal pain (6).
—–DRUG 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 (2.7 and 7).
- 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 (2.7 and 7).