Intuniv (guanfacine extended release) is used to treat attention-deficit hyperactivity disorder (ADHD) in kids ages 6 to 17 years old. It's not a controlled substance and can be used instead of stimulant medications for ADHD. Intuniv (guanfacine ER) belongs to the drug class called alpha-2A agonists. It comes as a tablet that you take by mouth once a day, either in the morning or at bedtime. Common side effects include sleepiness and tiredness. Taking it in the evening might help with these side effects. Intuniv (guanfacine ER) comes as brand-name and generic versions.
Attention-deficit hyperactivity disorder (ADHD) in children ages 6 to 17 years
Intuniv (guanfacine ER) is an alpha-2A agonist. It's not exactly clear how it works to treat ADHD. But researchers think it lowers how much norepinephrine gets released into parts of the brain that play a role in attention and focus. This is thought to help improve attention and behavior.
Source: DailyMed
Side effects that you should report to your care team as soon as possible:
Side effects that usually do not require medical attention (report to your care team if they continue or are bothersome):
A non-stimulant medication for ADHD
Can take alone or with other ADHD medications
Only taken once a day, either in the morning or at night
Not a controlled substance
Can make you feel sleepy or tired
Might take a few weeks to start working
Might not work as well for teens between 13 and 17 years old
Not approved for adults with ADHD
Swallow Intuniv (guanfacine ER) whole with a glass of water, milk, or other liquid. Don't crush, chew, or cut the tablets. Otherwise, it can cause too much medication to get released too fast and raise your risk of side effects. Talk to the prescriber if you have trouble swallowing the tablet whole.
Avoid taking Intuniv (guanfacine ER) with a high-fat meal. This can raise the level of medication in the body, which can lead to more side effects like sleepiness.
It's common for Intuniv (guanfacine ER) make you sleepy or tired. This can make it harder to think and react quickly. These side effects usually happen when you start treatment and when you first start taking a higher dose. Don't drive, use heavy machinery, or do anything that needs your full attention until you know how the medication affects you.
To lower the risk of feeling sleepy and tired from Intuniv (guanfacine ER), you'll first start with a lower dose of the medication. Your prescriber will slowly raise the dose over a few weeks. You can try taking the medication close to bedtime each night to help with these side effects. Talk to your prescriber if the sleepiness and tiredness doesn't get better over time.
Don't drink alcohol while taking Intuniv (guanfacine ER). Also stay away from other medications that make you sleepy like antihistamines and some antidepressants. Taking them together can make you extra sleepy or tired and possibly raise the risk of getting hurt.
Intuniv (guanfacine ER) can lower your blood pressure and make you feel dizzy. Stand up slowly after sitting or lying down to help prevent your blood pressure from dropping too low. Be sure to sit down if you feel dizzy. Talk to your prescriber if you get too dizzy.
Drink plenty of fluids and avoid getting overheated while taking Intuniv (guanfacine ER). Dehydration and heat exhaustion can put you at risk of low blood pressure and fainting.
Don't stop taking Intuniv (guanfacine ER) suddenly. This can cause your blood pressure to go up quickly. If you want to stop taking this medication, talk to your prescriber. They can help you stop Intuniv (guanfacine ER) safely by lowering your dose slowly over time.
Intuniv (guanfacine ER) can cause some serious health issues. This risk may be even higher for certain groups. If this worries you, talk to your doctor or pharmacist about other options.
Risk factors: Low blood pressure | Heart problems (e.g., low heart rate, heart block, heart disease) | Kidney problems | History of fainting | Dehydration | Taking other medications that lower blood pressure or slow the heart
Intuniv (guanfacine ER) can lower your blood pressure and heart rate. This can make you feel faint and dizzy. You're more likely to have lower blood pressure and heart rate when you first start the medication. It's also likely to happen when your prescriber raises the dose. But these side effects usually get better over time.
To keep you safe, your prescriber will check your blood pressure and heart rate while you're taking Intuniv (guanfacine ER). They'll be extra careful with dosing if you have health conditions that could get worse with low blood pressure or heart rate. They'll also be careful if you take medications that can cause the same side effects. An example is with blood pressure medications.
Talk to your prescriber if you feel very dizzy, tired, or out of breath while taking Intuniv (guanfacine ER).
Risk factors: Taking other medications that cause sleepiness | Drinking alcohol
Intuniv (guanfacine ER) can cause sleepiness. It can also make it hard to focus, think, and react. These side effects might get better as you get used to the medication. Talk to your prescriber if the side effects don't go away or start to become bothersome.
Avoid doing anything requires you to be alert, like driving a car or using machinery, until you know how Intuniv (guanfacine ER) affects you. Don't drink alcohol while taking this medication.
Risk factors: History of heart rhythm problems | Taking certain blood pressure medications, like beta blockers
Intuniv (guanfacine ER) can raise your risk of having an irregular heartbeat. This is more likely if you also take certain blood pressure medications. These include beta blockers, methlydopa, and clonidine.
Tell your prescriber about your medical history and the medications you take. They might raise your Intuniv (guanfacine ER) dose more slowly or check your vital signs more often if you're at risk of this side effect.
Stopping Intuniv (guanfacine ER) too quickly can cause a "rebound" effect. This can lead to high blood pressure. You might also have a fast heart rate, headache, or feel nervous or anxious.
Try not to miss any doses and don't stop taking Intuniv (guanfacine ER) without talking to your prescriber first. To lower the risk of this "rebound" effect, your prescriber will slowly lower the dose if you need to stop the medication.
The typical starting dose is 1 mg by mouth once daily, either in the morning or evening.
The prescriber will raise the dose weekly to a maintenance dose. This maintenance dose is based on your child's body weight, age, and other medications. The typical maintenance dose ranges from 2 mg to 7 mg daily.
The maximum dose for kids between 6 and 12 years old is 4 mg per day. The maximum dose for teens between 13 and 17 years old is 7 mg per day.
Allergy to guanfacine
Attention-deficit hyperactivity disorder (ADHD) in children ages 6 to 17 years
Attention-deficit hyperactivity disorder (ADHD)
Attention-deficit hyperactivity disorder (ADHD) in people ages 6 years and older
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