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Guanfacine Dosage

Medically reviewed by Drugs.com. Last updated on May 16, 2022.

Applies to the following strengths: 1 mg; 2 mg; 3 mg; 4 mg

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.

Renal Dose Adjustments

Dose adjustment(s) may be required; however, no specific guidelines have been suggested. Caution recommended.

Liver Dose Adjustments

Dose adjustment(s) may be required; however, no specific guidelines have been suggested. Caution recommended.

Dose Adjustments

ATTENTION DEFICIT HYPERACTIVITY DISORDER (ADHD):
Recommended Target Dose Ranges Based on Weight (0.05 to 0.12 mg/kg/day):


Switching from Immediate Release to Extended Release: Discontinue immediate release and titrate extended release following the recommended dosing schedule. Do not substitute on a milligram per milligram basis.

Dosage Adjustment with Concomitant Use of Strong CYP450 3A4 Inhibitors:

Dosage Adjustment with Concomitant Use of Strong CYP450 3A4 Inducers:

Precautions

Safety and efficacy have not been established in hypertensive patients younger than 12 years; safety and efficacy have not been established in Attention Deficit Hyperactivity Disorder (ADHD) patients younger than 6 years.

Consult WARNINGS section for additional precautions.

Dialysis

No adjustment recommended

Other Comments

Administration advice:
Extended release:


Monitoring:

Patient advice:

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.