Alpha-2 adrenergic agonist
Selectively stimulates central alpha-2A adrenergic receptors, reducing sympathetic outflow, which lowers blood pressure and enhances prefrontal cortical regulation of attention and impulse control.
Hypertension, attention-deficit/hyperactivity disorder (ADHD)
Tic disorders, sleep disturbances, agitation and aggression in neurodevelopmental disabilities (especially with hyperactivity or impulsivity)
Immediate-release tablets (Tenex), extended-release tablets (Intuniv)
Start at 1 mg p.o. nightly, titrate slowly based on clinical response, typical dose range 1–4 mg/day
1–4 mg/day
Immediate-release half-life approximately 10–17 hours; extended-release half-life approximately 17 hours. Metabolized hepatically (CYP3A4), excreted renally.
Drowsiness, headache, abdominal pain, dry mouth
Hypotension, bradycardia (monitor especially in elderly or cardiac patients)
Monitor blood pressure and heart rate regularly; assess sedation
None
Use caution in elderly patients due to increased risk of hypotension and orthostatic falls. Guanfacine may benefit individuals with neurodevelopmental disorders by improving attention and reducing tics. Dose adjustments may be necessary in hepatic impairment.