Guanfacine
Guanfacine is a prescription medication that acts as an alpha-2 adrenergic agonist. It is primarily used to treat high blood pressure (hypertension) in adults and has also gained approval for treating Attention Deficit Hyperactivity Disorder (ADHD) in children and adolescents. The medication works by reducing signals that tighten blood vessels, thereby lowering blood pressure, and in ADHD, it helps improve attention and impulse control.
Guanfacine is a blood pressure medication and ADHD treatment that works by affecting alpha-2 adrenergic receptors.
Key facts at a glance
- ATC
- C02AC02
- RxNorm
- 40114
- Generic
- Guanfacine
- Class
- atc-c02
- Brands
- Intuniv
- Availability
- rx
- Lactation
- unknown
- Routes
- oral
- Forms
- tablet
- Regions
- US, EU, CN, JP
- Monitoring
- —
This page is for informational purposes only.
Do not use this information to diagnose yourself or to replace a physician's advice. Always consult a qualified healthcare provider before starting, stopping, or changing any medication. If you believe you are experiencing a medical emergency, call your local emergency number immediately.
Dosage and administration
- Usual dose
- 1mg once daily
- Maximum
- consult physician
- Frequency
- once daily
- Instructions
- Follow physician instructions
- Duration limits
- as prescribed
- Monitoring
- standard
- Usual dose
- 1mg once daily
- Maximum
- consult physician
- Frequency
- once daily
- Instructions
- Follow physician instructions
- Duration limits
- as prescribed
- Monitoring
- standard
- Usual dose
- 1mg once daily
- Maximum
- consult physician
- Frequency
- once daily
- Instructions
- Follow physician instructions
- Duration limits
- as prescribed
- Monitoring
- standard
Overdose information
Special Populations
8 groupspregnancy
overallavoid if possible
use only if benefits outweigh risks to fetus
regular fetal monitoring recommended
Use with caution and monitor for adverse effects.
pregnancy
first trimesteravoid
avoid use during first trimester unless absolutely necessary
regular prenatal care and fetal monitoring
Use with caution and monitor for adverse effects.
lactation
breastfeedingdiscontinue or avoid
guanfacine passes into breast milk, consider discontinuing breastfeeding or stopping medication
monitor infant for excessive drowsiness, hypotonia, and feeding difficulties
Use with caution and monitor for adverse effects.
pediatric_age
children 6 17 yearsweight-based titration required
approved for ADHD in children 6-17 years, start at 1mg daily and titrate up to 4mg max
monitor blood pressure, heart rate, weight, and growth
geriatric
elderly 65 years and olderstart at lowest dose
use with caution due to increased sensitivity to hypotensive effects, start at 1mg
frequent blood pressure and heart rate monitoring
Use with caution and monitor for adverse effects.
renal_impairment
moderatereduce dose by 50%
use with caution, dose reduction recommended in moderate renal impairment
monitor renal function and blood pressure closely
Use with caution and monitor for adverse effects.
renal_impairment
severeavoid or use very low dose
use with extreme caution, consider alternative therapies
intensive monitoring of renal function and blood pressure
Use with caution and monitor for adverse effects.
hepatic_impairment
moderateuse with caution
metabolized in liver, use with caution in moderate hepatic impairment
monitor liver function tests and blood pressure
Use with caution and monitor for adverse effects.
Statistics and clinical data
Drug class
Pharmacological classification based on mechanism of action
FDA approval year
FDA approval for Intuniv (ADHD)
Primary indication
Primary therapeutic use in pediatric and adult patients
Secondary indication
Original indication under brand name Tenex
Guanfacine is FDA-approved for treating hypertension in adults and is also approved for ADHD management in children ages 6-17. It may be used alone or with other medications, and off-label uses include management of withdrawal symptoms and tic disorders.
As an alpha-2 adrenergic agonist, guanfacine binds to alpha-2 receptors in the brain and peripheral nervous system. This action reduces sympathetic nervous system activity, decreasing norepinephrine release, which leads to vasodilation (relaxation of blood vessels) and reduced heart rate, ultimately lowering blood pressure. In ADHD, it is thought to improve prefrontal cortex function and executive control.
Common side effects include drowsiness, dry mouth, dizziness, headache, and constipation. Guanfacine should not be stopped abruptly as this can cause rapid blood pressure rise (rebound hypertension). It may cause sedation, particularly when starting treatment, and patients should avoid operating heavy machinery until they know how the medication affects them. Alcohol and other sedatives may enhance drowsiness. Regular blood pressure monitoring is recommended during treatment.
Contraindications
Conditions and patient states where this medication should be avoided or used with caution.
Do not use (1)
Known allergy to this medication or its components
Use caution (1)
Consult healthcare provider for benefits vs risks assessment
Official drug label
WellAlly may earn a referral fee from linked resources at no extra cost to you. Editorial content is never influenced by commercial relationships.
This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.
This content is for general informational and educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of a qualified healthcare provider with any questions you have about a medical condition, and never disregard professional medical advice or delay seeking it because of something you read here.
If you think you may have a medical emergency, call your local emergency number or go to the nearest emergency department immediately.
Medically reviewed by WellAlly Editorial Team Last reviewed August 24, 2026. · Read our editorial policy