Guanfacine reduces nerve impulses in your heart and blood vessels. Guanfacine works by relaxing blood vessels, which lowers blood pressure and improves blood flow.

Guanfacine is used to treat high blood pressure (hypertension). It is sometimes given together with other blood pressure medications.

Guanfacine is also used to treat attention deficit hyperactivity disorder (ADHD) in children who are at least 6 years old.

Common side effects may include:

• mild dizziness or drowsiness;

• dry mouth;

• constipation; or

• weakness.

• hallucinations;

• chest pain, fast or slow heartbeats; or

• a light-headed feeling, like you might pass out

Guanfacine dosing information

Usual Adult Dose for Hypertension:

Initial dose: 1 mg orally once a day at bedtime; may increase to 2 mg once a day if satisfactory result not achieved after 3 to 4 weeks.

Comments: Adverse reactions increase significantly with doses above 3 mg/day.

Usual Pediatric Dose for Attention Deficit Disorder:

6 YEARS TO LESS THAN 18 YEARS:
Initial dose: 1 mg orally once a day, either in the morning or evening, at approximately the same time each day; may adjust in increments of no more than 1 mg/week.

Recommended target dose: 0.05 to 0.12 mg/kg/day (total daily dose between 1 and 7 mg) once a day, depending on clinical response and tolerability

Maximum dose: 6 to 12 years: Doses above 4 mg/day have not been evaluated; 13 to 17 years: Doses above 7 mg/day have not been evaluated.

Comments: Attention Deficit Hyperactivity Disorder (ADHD) may require treatment for an extended period of time; healthcare providers should periodically reevaluate treatment and adjust dose as needed.

Use: Treatment of ADHD as monotherapy and as adjunctive therapy to stimulant medications.

Usual Pediatric Dose for Hypertension:

12 YEARS OR OLDER:
Initial dose: 1 mg orally once a day at bedtime; may increase to 2 mg once a day if satisfactory result not achieved after 3 to 4 weeks.

Comments: Adverse reactions increase significantly with doses above 3 mg/day.