Guanfacine (Intuniv).

What is Guanfacine (Intuniv)?

Guanfacine is a centrally acting selective adrenergic receptor agonist. While the immediate-release form was originally approved to treat high blood pressure (hypertension), the extended-release formulation (Intuniv) is specifically approved for ADHD.

By targeting receptors in the prefrontal cortex, the part of the brain responsible for regulating attention, behavior, and impulse control, it helps to strengthen cognitive functions. It is a non-stimulant, meaning it is not a controlled substance and is not associated with the same risk of abuse or dependency as traditional stimulants.

Drug Identifiers

• Brand Name: Intuniv (extended-release), Tenex (immediate-release)
• Generic Name: Guanfacine hydrochloride

Physical Description (Intuniv Extended-Release Tablets)

Intuniv is available as prolonged-release, film-coated tablets in four different strengths, with distinguishing colors and markings:

• 1 mg: Round, white to off-white, debossed with ‘1MG’ on one side and ‘503’ on the other.
• 2 mg: Oblong, white to off-white, debossed with ‘2MG’ on one side and ‘503’ on the other.
• 3 mg: Round, green, debossed with ‘3MG’ on one side and ‘503’ on the other.
• 4 mg: Oblong, green, debossed with ‘4MG’ on one side and ‘503’ on the other.

Guanfacine is FDA-approved to Treat

Note: The immediate-release formulation (Tenex) is FDA-approved to treat hypertension (high blood pressure).

Common Off-Label Uses

While Intuniv is only officially approved for pediatric ADHD, healthcare providers may prescribe it off-label for other conditions based on clinical judgment and research:

• Adult ADHD: Often used in adults who cannot tolerate or do not respond to traditional stimulants.

• Tic Disorders (e.g., Tourette Syndrome).

• Anxiety Disorders, including Generalized Anxiety Disorder (GAD).

• Post-Traumatic Stress Disorder (PTSD): May help with hyperarousal, emotional reactivity, and sleep disturbances (like nightmares) associated with trauma.

• Disruptive Mood Dysregulation Disorder (DMDD) and conditions involving mood lability, irritability, and aggression in children and adolescents.

Side Effects

Common side effects often occur when first starting or increasing the dose and may lessen over time.

Common Side Effects:

• Sleepiness
• Fatigue,
• Dizziness,
• Headache
• Abdominal pain
• Nausea
• Dry mouth
• Constipation
• Insomnia
• Weight increase

Serious & Less Common Side Effects

(Seek immediate medical attention)

• Fainting
• Severe Drowsiness
• Hypersensitivity reaction (rash, hives, swelling)

Important Note: Due to the risk of lowered blood pressure and heart rate, vital signs should be monitored by a healthcare provider prior to starting therapy, following dose increases, and periodically during treatment.

Contraindications

Intuniv is contraindicated (should not be used) in patients with a history of a hypersensitivity reaction to guanfacine or any of its inactive ingredients (e.g., rash, swelling).

Dosage of Intuniv

Dosage for Intuniv is highly individualized based on the patient’s weight, clinical response, and tolerability.

• Starting Dose: Typically 1 mg once daily, taken either in the morning or evening.

• Titration: The dose is usually adjusted slowly, in increments of no more than 1 mg per week.

• Target Dose Range: Generally 0.05 to 0.12 mg/kg/day, with a maximum recommended dose of 4 mg/day for children aged 6-12 and 7 mg/day for adolescents aged 13-17.

• Administration: Must be swallowed whole and must not be crushed, chewed, or broken. It can be taken with or without food, but avoid taking it with a high-fat meal as this can significantly increase the drug’s absorption and potential side effects.

Missed Dose

If you happen to miss a dose of Intuniv, take the missed dose as soon as you remember, provided it is still within a few hours of your scheduled time. However, if it is almost time for your next dose (generally considered more than 12 hours since your scheduled time), you should skip the missed dose entirely and simply resume your regular dosing schedule; never double your dose to compensate for the one you missed.

If you miss more than two doses in a row, it is important to contact your healthcare provider for guidance, as they may advise you on a schedule to slowly re-titrate your dose to minimize the risk of potential side effects, such as rebound hypertension.

Questions to Ask Your Doctor About Guanfacine

• What are the signs of low blood pressure or a slow heart rate that I should watch for?

• Should I take this medication in the morning or the evening? Does it matter if I take it with food?

• How long will it take to know if this medication is working for my/my child’s symptoms?

• What is the proper way to discontinue this medication if we decide to stop taking it?

• Does this drug interact with any of my current over-the-counter or herbal supplements?

Guanfacine Frequently Asked Questions