Guanfacine for Anxiety Treatment

Introduction to Guanfacine

Guanfacine is FDA-approved for attention-deficit/hyperactivity disorder (ADHD) and hypertension, but not for anxiety disorders, according to the American Academy of Child and Adolescent Psychiatry 1, 2, 3
It works as an α2A-adrenergic receptor agonist, enhancing noradrenergic neurotransmission in the prefrontal cortex, which strengthens top-down regulation of attention, thought, and working memory, as noted by the American College of Clinical Pharmacology 4, 5

Current guidelines from the American Academy of Child and Adolescent Psychiatry mention α-agonists (clonidine, guanfacine) are "sometimes used for management of anxiety" in children with intellectual disability/developmental disorders, but note there are no trials investigating this specific indication 6, 7
SSRIs (fluoxetine, sertraline) remain the treatment of choice for anxiety based on evidence in typically developing youth, according to the American Academy of Child and Adolescent Psychiatry 6, 7
The American College of Clinical Pharmacology recommends that guanfacine be considered for anxiety in specific scenarios, such as when first-line treatments have failed or are contraindicated 6

Most common adverse effects of guanfacine include somnolence, fatigue, irritability, insomnia, nightmares, dry mouth, constipation, and dizziness, as reported by the American College of Clinical Pharmacology 5
Cardiovascular effects include potential hypotension and bradycardia, and administration in the evening is generally preferable due to the frequent occurrence of somnolence/fatigue, according to the American College of Clinical Pharmacology 5, 8, 9
Warnings exist regarding hypotension/bradycardia, somnolence/sedation, discontinuation reactions, allergic reactions, and cardiac conduction abnormalities, as noted by the American College of Clinical Pharmacology 5

The American Academy of Child and Adolescent Psychiatry recommends starting with stimulant medication for ADHD first, even when anxiety is present, as early concerns that ADHD patients with comorbid anxiety had less robust responses to stimulants have not been replicated in more extensive clinical trials 10
The American Academy of Child and Adolescent Psychiatry suggests assessing whether treating ADHD alone resolves the anxiety symptoms, as the reduction in morbidity caused by ADHD symptoms can have substantial impact on anxiety symptoms 10

The American Academy of Child and Adolescent Psychiatry recommends pursuing psychosocial intervention for anxiety first if anxiety remains problematic after ADHD symptoms improve 10
The American Academy of Child and Adolescent Psychiatry suggests adding an SSRI to the stimulant if anxiety does not respond to non-pharmacological treatment or is severe 10

Guanfacine may be appropriate in ADHD patients with comorbid tic disorders or Tourette's syndrome, where it addresses both ADHD and tics 10