From the Research
The usual effective dose of guanfacine for adults is 4-6 mg taken once daily, as demonstrated by the most recent and highest quality study 1.
Key Considerations
- The medication is often taken at bedtime due to its sedative effects.
- For attention deficit hyperactivity disorder (ADHD) in adults, the target dose is typically 4-6 mg daily, with careful titration to minimize side effects, as shown in the study 1.
- Extended-release formulations are preferred for ADHD treatment with once-daily dosing.
- Guanfacine works as a centrally-acting alpha-2A adrenergic receptor agonist, reducing sympathetic outflow from the brain and improving prefrontal cortex functioning.
- Patients should be aware that abrupt discontinuation can cause rebound hypertension, so the medication should be tapered gradually when stopping treatment.
Supporting Evidence
- A randomized, double-blind, placebo-controlled study 1 demonstrated the efficacy and safety of guanfacine extended-release in adults with ADHD, with a significant improvement in ADHD symptoms and no major safety concerns.
- The study 1 also showed that the most common treatment-emergent adverse events were somnolence, thirst, blood pressure decrease, nasopharyngitis, postural dizziness, and constipation, with most being mild to moderate in severity.
- Another study 2 supported the long-term safety and efficacy of guanfacine extended-release in adults with ADHD, with significant improvements in ADHD symptoms, quality of life, and executive functioning.