Intuniv (Guanfacine) - Oral

What Is Intuniv?

Intuniv (guanfacine) is a prescription non-stimulant treatment for attention-deficit/hyperactivity disorder (ADHD). It can be used as a monotherapy (single treatment) or as an add-on (adjunctive) treatment to stimulant medications. It can also be used to treat hypertension (high blood pressure).

Intuniv is a central alpha-2A adrenergic receptor agonist. It works on receptors in the prefrontal cortex (PFC) in the brain to enhance functioning. The PFC plays a role in cognitive behavior, including attention and impulsivity.

Intuniv is available as an extended-release tablet to be taken by mouth.

What Is Intuniv Used For?

The Food and Drug Administration (FDA) approved Intuniv to treat ADHD as either a monotherapy or adjunctive therapy to stimulant medications. It helps to improve common symptoms associated with ADHD, such as concentration difficulties, distractedness, and impulsiveness.

Intuniv may sometimes be prescribed with another type of ADHD medication known as a stimulant. Stimulants are typically used as first-line treatment for people with ADHD.

In some cases, nonstimulants may be the preferred choice of treatment if you have:

• Tic disorder or Tourette's syndrome
• Disruptive behavior disorder
• Substance use disorder
• Sleep disturbances

Often, ADHD medications like Intuniv are used in concert with behavioral therapy. For children with ADHD, behavioral management training for the parents is also involved.

Guanfacine is also used to treat high blood pressure. As a blood-pressure-lowering agent, it works to decrease heart rate and relax the blood vessels to allow blood to flow through them more easily. This helps lower blood pressure.

How to Take Intuniv

The following are recommendations for using Intuniv; however, always take it as ordered by your healthcare provider. These recommendations include:

• Take it once a day at the same time, either morning or evening. You may want to take it in the evening if you experience side effects of fatigue and drowsiness.
• Do not take with a high-fat meal, as this can increase exposure to guanfacine. Instead, take it with a light meal or without food.
• Swallow the extended-release tablets whole with a small amount of water or another liquid; do not break, chew, or crush them.
• Do not take this medication with grapefruit or grapefruit juice.

Storage

Follow these guidelines for storage:

• Dispose of unused medication through a pharmacy or a medication disposal company.
• Do not open the medication bottle until ready to give the first dose. 
• Keep away from children.
• Keep away from moisture (e.g., avoid storing it in the bathroom)
• Once expired, dispose of medication.
• Protect from light, extreme heat, and extreme cold
• Store in the original airtight container

Off-Label Uses

Intuniv can be prescribed off-label (for a non-FDA approved use) for:

• Post-traumatic stress disorder (PTSD)
• Insomnia
• Oppositional defiant disorder
• Pervasive developmental disorder
• Motor tics

What Are the Side Effects of Intuniv?

This is not a complete list of side effects, and others may occur. A healthcare provider can advise you on side effects. If you experience other effects, contact your pharmacist or a healthcare provider. You may report side effects to the FDA at fda.gov/medwatch or 800-FDA-1088.

Common Side Effects

As with all medications, side effects can occur while taking Intuniv. Common and less severe side effects include:

• Decreased appetite
• Decreased blood pressure
• Dizziness
• Fatigue
• Headaches
• Irritability
• Lethargy
• Nausea
• Somnolence (drowsiness)
• Upper abdominal pain

Severe Side Effects

Call your healthcare provider immediately if you have serious side effects. Call 911 if your symptoms feel life-threatening or if you think you’re having a medical emergency. Serious side effects can include the following:

• Psychiatric reactions, such as agitation, anxiety, and depression
• Asthenia (abnormal weakness)
• Asthma
• Atrioventricular (AV) block, also called a heart block (a condition in which the heart's electrical signal slows or stops completely due to blockage)
• Convulsion
• Dyspepsia (indigestion)
• Hypertension
• Sinus arrhythmia, or when your heartbeat is too fast, too slow, or irregular

Dosage: How Much Intuniv Should I Take?

Modifications

Due to the possible effects of this medication, there may be changes to how it is used. The following circumstances may necessitate a dosage adjustment or extra caution when taking Intuniv:

• Severe kidney disease: As kidney function decreases, it becomes more difficult for the body to eliminate guanfacine from the body. Depending on your level of kidney function, you may need a dose adjustment with Intuniv.
• Severe liver disease: Guanfacine is cleared from the body through the kidneys and liver. Significant liver impairment may require a different dose of Intuniv.
• Breastfeeding: It is unknown whether guanfacine passes into human breast milk. Use caution while taking Intuniv if you are breastfeeding or plan to breastfeed, and watch for signs of sedation in breastfed infants. Consult your healthcare provider before breastfeeding.

Missed Dose

Take the missed dose as soon as you remember it. However, if it is almost time for the next dose, skip the missed dose and continue your regular dosing schedule. Do not take a double dose to make up for a missed one.

Call your healthcare provider if you miss two or more consecutive doses of the extended-release tablets.

Overdose: What Happens If I Take Too Much Intuniv?

Inform your healthcare provider immediately if you take too much Intuniv. Symptoms of an overdose may include:

• Blurred vision
• Constricted pupils
• Dizziness
• Drowsiness
• Fainting
• Lack of energy
• Slow heart rate

Precautions

What Are Reasons I Shouldn’t Take Intuniv?

There are a few reasons why you might not be able to take Intuniv, including:

• Pregnancy: There is limited data on whether this medication crosses the placenta. Talk to your healthcare provider if you plan to become pregnant or become pregnant while on this medication to discuss the next steps for your treatment.
• Breastfeeding: Guanfacine has not been studied in breastfeeding for humans. You may wish to change your medication plan if you are concerned about adverse effects in your breastfeeding infant. Talk to your healthcare provider to determine the best plan for you and your baby.
• Allergy: You should not take Intuniv if you have a history of hypersensitivity to guanfacine or its other ingredients.
  

What Other Medications Interact With Intuniv?

Other medications can interact with Intuniv. In some cases, you can still use these medications together. Ultimately, your healthcare provider may need to change the drug's doses or monitor for potential side effects.

Watch for potential central nervous system (CNS) side effects when taking Intuniv with valproic acid. Taking these medications together can increase concentrations of valproic acid. Additionally, taking guanfacine with other antihypertensive drugs can cause side effects such as hypotension (low blood pressure) and syncope (fainting) due to the additive blood-pressure-lowering effects.

Monitor for increased somnolence or sedation when taking Intuniv with the following:

• Alcohol
• Antidepressants, including selective serotonin reuptake inhibitors (SSRIs) like Prozac (fluoxetine) and tricyclic antidepressants (TCAs) like Norpramin (desipramine), among others. Combined use with antidepressants may also inhibit the blood pressure-lowering effects of guanfacine
• Barbiturates such as phenobarbital and Mysoline (primidone)
• Sedatives, including benzodiazepines such as Xanax (alprazolam) and sleeping pills such as Ambien (zolpidem)

Examples of other medications that interact with Intuniv are:

• Dilantin (phenytoin)
• Sporanox (itraconazole)
• Ketoconazole
• Mycobutin (rifabutin)
• Rifampin
• Norvir (ritonavir)

This is not a complete list of drug interactions that can occur with Intuniv. Be sure to always tell your healthcare provider about your current use of prescription and over-the-counter medications, supplements, and herbal supplements. While some drugs pose minor interaction risks, others may outright contraindicate use or prompt careful consideration as to whether the pros of treatment outweigh the cons in your case.

Ask your healthcare provider or pharmacist for a comprehensive list of potential drug interactions.

What Medications Are Similar?

Intuniv is a nonstimulant medication used to treat ADHD. It belongs to a class of medications called alpha-2 adrenergic agonists. The only other ADHD drug in this class is Kapvay (clonidine).

Like Intuniv, clonidine is an extended-release medication used to improve ADHD symptoms. Clonidine can be used as a monotherapy or in addition to stimulant therapy.

Guanfacine and clonidine are pharmacologically similar, sharing the same mechanism of action. However, guanfacine is approximately 10 times less potent than clonidine and is metabolized differently. Still, adverse effects are generally similar between the two medications.

How Can I Stay Healthy While Taking Intuniv?

Intuniv is a once-a-day non-stimulant medication used to treat ADHD in adults and children between the ages of 6 and 17. This medication can be used either alone or in conjunction with stimulant ADHD medications such as Concerta (methylphenidate), Focalin (dexmethylphenidate), Adderall XR (amphetamine and dextroamphetamine), or Vyvanse (lisdexamfetamine).

Often, nonstimulant therapy is just one part of a multi-pronged approach to managing ADHD symptoms. Treatment is often individualized, as there is no one-size-fits-all approach. Other medications or different types of therapy, such as behavior therapy or psychotherapy, may also be part of your treatment plan.

If multiple medications are part of your treatment, it may be challenging to remember when to take each dose. Because Intuniv is an extended-release formulation, it only needs to be taken once daily. However, other medications may need to be taken several times daily. Try using a pillbox or medication app reminder to keep track of your dosing schedule.

Before starting any new medications or using complementary treatments, ask your healthcare provider or pharmacist about the potential interaction risks. Remember that it might take time to adjust to your treatment regimen and could take several weeks before noticing any improvement. Don't hesitate to communicate how you feel to your healthcare team; they can help manage side effects or switch to a different therapy if needed.