Stahl's Essential Psychopharmacology Online
In Collaboration With
Guanfacine
Therapeutics
Brands
• Tenex, Intuniv
Generic?
Yes (except extended release)
Class
• Antiadrenergic, alpha-2 agonist
Commonly Prescribed for
(FDA approved in bold)
• Hypertension
• Gilles de la Tourette syndrome (GTS)
• Tics
• Attention deficit hyperactivity disorder (ADHD)
• Neuropathic pain
• Opioid detoxification
• Alcohol withdrawal
• Hypertensive “urgency”
• Post-traumatic stress disorder
How the Drug Works
• Alpha-2 adrenergic agonist. Reduces sympathetic output from CNS, which decreases cardiac output, peripheral vascular resistance,
and blood pressure
• Specifically targets alpha-2 receptors in the brainstem vasomotor center, decreasing presynaptic calcium levels and the release
of norepinephrine
• Its effect in GTS and ADHD may be due to actions at the level of the prefrontal cortex
How Long Until It Works
• Hypertension, withdrawal - less than 2 hours
• GTS - weeks to months
If It Works
• In neurologic disorders, such as tics, continue to assess effect of the medication to see if it is still needed
If It Doesn't Work
• GTS/tics - Neuroleptics are often effective, but their use should be reserved for patients with significant social isolation
or embarrassment
Best Augmenting Combos for Partial Response or Treatment-Resistance
• In hypertension, combine with treatments less likely to cause orthostasis (angiotensin-converting enzyme inhibitors, diuretics)
• Tics and GTS symptoms may change over time. Many patients improve with age. Behavioral and psychological therapy are useful,
and education and reassurance are all that is needed in mild cases
• Identify and treat comorbid conditions such as ADHD or obsessive-compulsive disorder
Tests
• Monitor blood pressure and pulse