does guanfacine (intuniv) have a black box warning?

no. the guanfacine extended-release label has no boxed warning. it has four warnings: dose-related falls in blood pressure and heart rate with fainting reported, sleepiness and sedation, worsening of heart conduction problems in people who already have them, and rebound high blood pressure if it is stopped abruptly, with hypertensive encephalopathy reported. it is not a controlled substance and the label says it has no known potential for abuse or dependence.

what happens if you stop guanfacine suddenly?

the label says abrupt stopping has caused clinically significant and persistent rebound high blood pressure and faster heart rate, and that hypertensive encephalopathy has been reported, mostly after high doses were stopped and often with a stimulant also taken. its instruction is to taper the daily dose by no more than 1 mg every 3 to 7 days while blood pressure and pulse are monitored, and it says patients should not stop without consulting their prescriber.

how well does guanfacine work for adhd?

in the label’s trials in children and adolescents, adhd rating scale scores, starting near 36 to 43, fell 5.4 to 10.0 points more than placebo on guanfacine alone, and 4.5 to 5.3 points more when it was added to a stimulant. a 2018 network meta-analysis of 133 trials found it better than placebo on clinician ratings in children and adolescents, but not on the teacher ratings available, and found children more likely to stop it because of side effects than placebo.

is guanfacine approved for adults?

the indication on the extended-release label is adhd, as monotherapy or added to a stimulant, but every efficacy trial on the label enrolled children and adolescents aged 6 to 17, the label reports no adult efficacy trial, and it says safety and efficacy have not been established under age 6 or in older people. whether to use it in an adult is a question for the prescriber, with that gap in view.

what are the most common guanfacine side effects?

sleepiness, by a wide margin: in the fixed-dose trials 28% at 1 mg rising to 51% at 4 mg, against 11% on placebo, and over half of children and adolescents in the flexible-dose trials. then fatigue, headache, abdominal pain, low blood pressure, dizziness, nausea, dry mouth, irritability and nightmares. stopping because of side effects rose from 3% at 1 mg to 18% at 4 mg.

is guanfacine a stimulant or a controlled substance?

no to both. the label calls it a central alpha-2a adrenergic receptor agonist, the same receptor family as some blood-pressure drugs, and says it is not a controlled substance and has no known potential for abuse or dependence. that is why its warnings are about blood pressure, heart rate and sleepiness rather than misuse.

Medication approval journey

guanfacine (Intuniv)

Approved for ADHD in children and adolescents 6 to 17, as monotherapy or adjunct to stimulants

page first published 2026-09-01 · last updated 2026-10-13

Also answers to “the career change” — its codename in our videos and posts. The full codebook

FDA approvedNon-stimulant ADHD medicationTaper risk: high

How this page reads

The page as written, with the clinical terms

Plain language uses the same facts, the same numbers and the same caveats. It does not leave anything out. Quotes from the FDA label are never reworded in either setting.

Before you stop or change your guanfacine dose

Stopping abruptly can be dangerous — never do it without medical supervision

Clonidine and guanfacine must not be stopped abruptly — rebound high blood pressure is a real risk. Any change should be prescriber-supervised.

what the guanfacine warnings mean

label facts below are read from the guanfacine extended-release tablets FDA label on DailyMed, set id ab2e3597-14fc-4614-ae87-0d1d18188a68, version 2, effective august 3, 2026, the version the dossier above cites. it is a repackaged generic of intuniv (the extended-release adhd tablet, nda 022037), not the older immediate-release blood-pressure tablet, and it carries intuniv’s full trial and side-effect tables. the brackets name the label section. every source is linked at the end of this section. last checked 2026-10-13.

guanfacine extended-release was approved on september 2, 2009 under the brand intuniv, and its label approves one thing: the treatment of adhd, "as monotherapy and as adjunctive therapy to stimulant medications" [label 1; approval]. it is not a stimulant. the label calls it a central alpha-2a adrenergic receptor agonist, a drug that acts on the same receptor as the blood-pressure medicines, and that is the key to its warnings: it lowers blood pressure and heart rate, it makes people sleepy, and stopping it suddenly can push blood pressure up [label 1, 5]. it is "not a controlled substance and has no known potential for abuse or dependence" [label 9.1]. every efficacy trial on the label was in children and adolescents aged 6 to 17; the label reports no efficacy trial in adults, says safety and efficacy under 6 "have not been established", and says the same for older people [label 8.4, 8.5, 14]. it carries no boxed warning. the federal survey this site uses for a scale line last gives a usable count in 2019: about 690,800 americans (standard error about 124,400) filled a guanfacine prescription that year, about 4.6 million prescriptions in all, against about 517,100 people in 2014; from 2020 to 2024 too few respondents reported it (6 in 2024) for ahrq to publish a figure. the survey counts guanfacine by name, so that figure does not separate this tablet from the older immediate-release one [meps]. this section says what each warning means in plain words, what the label says about stopping, what the seven trials measured and how large the effects were, which side effects the label counts and how often, and what independent research has found, in both directions. every number is from the label or a study in the library, and each source is linked at the end.

this is information to take to a prescriber. nothing here is a reason to start, stop or change a dose on your own; with this drug the label says abrupt stopping can cause rebound high blood pressure, and the taper language quoted below is the label’s, not ours.

no boxed warning, and what the label warns about instead

unlike the stimulants, whose labels carry a boxed warning on abuse and misuse that the fda updated in 2023 [stimulant-warning], and unlike atomoxetine, the other non-stimulant, whose label opens with a boxed warning on suicidal thoughts and behaviors in children [atomoxetine-label; compare-atomoxetine], the guanfacine extended-release label has no boxed warning [label]. it has four warnings, all of which follow from how the drug works:

low blood pressure, slow heart rate and fainting: the drug "can cause dose-dependent decreases in blood pressure and heart rate", and "orthostatic hypotension and syncope have been reported". the label asks for heart rate and blood pressure to be measured before starting, after each dose increase and periodically after that, for slow titration in anyone with a history of low blood pressure, heart block, slow heart rate, heart or vascular disease, stroke or chronic kidney failure, and for patients prone to fainting to avoid becoming dehydrated or overheated [label 5.1].
sleepiness and sedation: "somnolence and sedation were commonly reported adverse reactions". the label cautions against driving or operating heavy equipment until a person knows how they respond, asks prescribers to consider the added sedation of other depressant drugs, and says to avoid alcohol [label 5.2].
heart conduction: the drug "may worsen sinus node dysfunction and atrioventricular (av) block, especially in patients taking other sympatholytic drugs" [label 5.3].
rebound high blood pressure on stopping, set out in the next block [label 5.4].

what the label says about stopping

quoted so that it is the label’s and not ours: "in post marketing experience, abrupt discontinuation of guanfacine extended-release tablets has resulted in clinically significant and persistent rebound hypertension above baseline levels and increases in heart rate. hypertensive encephalopathy has also been reported in association with rebound hypertension" [label 5.4]. in those reports "high-dosage guanfacine was discontinued; concomitant stimulant use was also reported, which may potentially increase hypertensive response upon abrupt discontinuation". the label adds a point specific to children: they "commonly have gastrointestinal illnesses that lead to vomiting, and a resulting inability to take medications, so they may be especially at risk" [label 5.4].

the instruction: "taper the daily dose in decrements of no more than 1 mg every 3 to 7 days to minimize the risk of rebound hypertension", with blood pressure and pulse monitored while the dose comes down, and patients and caregivers "instructed not to discontinue guanfacine extended-release tablets without consulting their health care provider" [label 2.5]. even with a taper, the trials saw an average rise of about 3 mmhg in blood pressure and 5 beats a minute in heart rate above the original baseline, and in the maintenance trial the estimated average time to get back to baseline was six to twelve months; those rises "were not considered serious", though "individuals may have larger increases than reflected by the mean changes" [label 6.1]. after two or more missed doses in a row, the label says to consider re-titrating rather than going straight back to the old dose [label 2.6].

what the trials measured, in whom, and for how long

the label rests on seven placebo-controlled trials, all in children and adolescents aged 6 to 17: five short trials of guanfacine alone, one 8-week trial added to a stimulant, and one long-term trial of staying on it [label 14]. every one used the clinician-rated adhd rating scale (adhd-rs-iv), with hyperactive-impulsive and inattentive subscales; average starting totals in these trials sat between about 36 and 43 [label 14, tables 16, 17].

the two fixed-dose trials ran 5 and 6 weeks in 345 and 324 children and adolescents. against placebo, scores fell by 7.4, 7.5 and 10.0 more points at 2, 3 and 4 mg in the first trial, and by 6.8, 5.4, 7.3 and 7.9 more points at 1, 2, 3 and 4 mg in the second; every dose beat placebo [label table 16]. placebo itself was large: an 8.5-point drop in the first trial and 12.7 in the second. the label then adds a sentence most summaries leave out: analysed by age, the effect was statistically significant "only in the 6-12 age subgroup". adolescents were about a quarter of those enrolled and over half of them (55%) got a low dose for their weight, so the label says the data "may not have been sufficient to demonstrate efficacy in the adolescent patients" [label 14].

three flexible-dose trials followed. in 340 children aged 6 to 12, scores fell 9.4 more points than placebo with a morning dose and 9.8 with an evening dose; in 314 adolescents aged 13 to 17 over 15 weeks, 6.0 more points; and in 337 children and adolescents, 8.9 more points [label table 17]. the adolescent trial dosed by weight, up to 7 mg, and did show an effect in that age group [label 14]. in the add-on trial, 455 children and adolescents whose stimulant was not working well enough took guanfacine or placebo alongside the stimulant for 8 weeks; scores fell 4.5 (morning) and 5.3 (evening) more points than placebo plus stimulant [label table 17]. in the maintenance trial, 526 children and adolescents started on open-label guanfacine, 315 who responded were randomised to stay on it or switch to placebo for 26 weeks, and fewer of those who stayed on it met the definition of treatment failure; the label shows that result only as a curve and prints no percentages [label 14].

side effects, with the label’s numbers

sleepiness dominates every table. in the two fixed-dose trials, somnolence (which the label counts as somnolence, sedation and hypersomnia together) rose with dose: 28% at 1 mg, 30% at 2 mg, 38% at 3 mg and 51% at 4 mg, against 11% on placebo; fatigue was 14% against 3%, and low blood pressure 7% against 3% [label table 3]. in the flexible-dose trial in children, somnolence was 56% against 15%; in the adolescent trial, 54% against 23% [label tables 6, 9]. added to a stimulant, it was 18% against 7% [label table 11]. other figures above placebo in the fixed-dose trials: headache 23% against 19%, abdominal pain 11% against 9%, dizziness 6% against 4%, nausea 6% against 2%, dry mouth 4% against 1%, and nightmares 2% against 0% [label tables 3, 5].

stopping because of side effects also rose with dose: 3% on placebo, and 3%, 7%, 10% and 18% at 1, 2, 3 and 4 mg, with sleepiness the commonest reason (11% at 4 mg) [label table 4]. the average falls in blood pressure and heart rate were largest at 4 mg (8.2 mmhg systolic, 8.6 beats a minute) and "usually modest and asymptomatic; however, hypotension and bradycardia can occur"; fainting occurred in 1% of children and adolescents across the programme, mostly in the long open-label studies [label 6.1]. on growth, the label reports similar growth to normative data and a mean weight gain of 0.5 kg over placebo [label 6.1]. after approval, reports added hallucinations, confusion, palpitations, blurred vision and the rebound hypertension and hypertensive encephalopathy above [label 6.2]. in overdose the label describes low blood pressure, drowsiness, lethargy and slow heart rate, sometimes after an early rise in blood pressure, and asks that a child who becomes lethargic be watched for up to 24 hours because low blood pressure can come late [label 10].

two practical label points. a high-fat meal raised peak levels by about 75%, so the label says not to take it with one; and the tablet must be swallowed whole, because crushing or chewing speeds the release [label 2.1, 12.3]. it is not interchangeable milligram for milligram with immediate-release guanfacine, which reaches much higher peak levels [label 2.3]. guanfacine is broken down by the liver enzyme cyp3a4, so strong or moderate inhibitors of that enzyme such as ketoconazole or fluconazole call for half the dose, and inducers such as rifampin or carbamazepine may call for up to double [label 2.7, 7].

what the research says, in both directions

a limit to state first: this site’s library holds no row tagged guanfacine yet. the research below is the label’s own trials and the one cross-drug review in the library that includes it.

in favour. all seven label trials beat placebo on their main measure, including in the add-on trial for children whose stimulant alone was not enough, and in the 26-week trial of staying on it [label 14]. the largest network meta-analysis of adhd medicines, 133 double-blind trials, found that on clinician ratings in children and adolescents at about 12 weeks "all included drugs were superior to placebo", guanfacine among them [cortese-2018]. it has no abuse potential on its label and is not a controlled substance, which matters for families worried about misuse [label 9.1].

against, or smaller than it sounds. the same meta-analysis found that on teacher ratings only methylphenidate and modafinil beat placebo among the comparisons available, and that guanfacine was the one drug besides amphetamines that children and adolescents were more likely to stop because of side effects than placebo (odds ratio 2.64, 95% ci 1.20 to 5.81); the authors recommended methylphenidate as the first choice for children and adolescents [cortese-2018]. the trials were 5 to 15 weeks long except the maintenance trial, the label says doses above 4 mg have not been evaluated in children aged 6 to 12 or above 7 mg in adolescents, and the fixed-dose trials could not show an effect in adolescents at the doses many of them got [label 2.2, 14]. there is no adult efficacy trial on the label [label 14].

questions to ask your prescriber about guanfacine

each one comes from a warning or a study above. they are questions, not instructions; the answers depend on a history nobody here has.

the label asks for heart rate and blood pressure before starting, after each dose increase, and periodically. when will those be checked, and what numbers would make us change course?
if we ever reduce or stop it, the label says no more than 1 mg every 3 to 7 days, with blood pressure watched. what would that schedule look like here?
children often miss doses when they are vomiting with a stomach bug, and the label says that puts them especially at risk of rebound high blood pressure. what should we do on a day the dose cannot be kept down?
sleepiness reached half of children at 4 mg in the trials. if it shows up, is it the dose, the timing, or something else?
the trials on the label are in ages 6 to 17. if i am an adult, what evidence is this prescription based on?
is anything else in my life lowering blood pressure or heart rate, or slowing the liver enzyme cyp3a4, such as an antifungal? the label names both.
this is being added to a stimulant. the label’s add-on trial found a 4.5 to 5.3 point extra drop on the rating scale, from a starting score near 37. what change would tell us it is worth it?

questions people ask

does guanfacine (intuniv) have a black box warning?: no. the guanfacine extended-release label has no boxed warning. it has four warnings: dose-related falls in blood pressure and heart rate with fainting reported, sleepiness and sedation, worsening of heart conduction problems in people who already have them, and rebound high blood pressure if it is stopped abruptly, with hypertensive encephalopathy reported. it is not a controlled substance and the label says it has no known potential for abuse or dependence.
what happens if you stop guanfacine suddenly?: the label says abrupt stopping has caused clinically significant and persistent rebound high blood pressure and faster heart rate, and that hypertensive encephalopathy has been reported, mostly after high doses were stopped and often with a stimulant also taken. its instruction is to taper the daily dose by no more than 1 mg every 3 to 7 days while blood pressure and pulse are monitored, and it says patients should not stop without consulting their prescriber.
how well does guanfacine work for adhd?: in the label’s trials in children and adolescents, adhd rating scale scores, starting near 36 to 43, fell 5.4 to 10.0 points more than placebo on guanfacine alone, and 4.5 to 5.3 points more when it was added to a stimulant. a 2018 network meta-analysis of 133 trials found it better than placebo on clinician ratings in children and adolescents, but not on the teacher ratings available, and found children more likely to stop it because of side effects than placebo.
is guanfacine approved for adults?: the indication on the extended-release label is adhd, as monotherapy or added to a stimulant, but every efficacy trial on the label enrolled children and adolescents aged 6 to 17, the label reports no adult efficacy trial, and it says safety and efficacy have not been established under age 6 or in older people. whether to use it in an adult is a question for the prescriber, with that gap in view.
what are the most common guanfacine side effects?: sleepiness, by a wide margin: in the fixed-dose trials 28% at 1 mg rising to 51% at 4 mg, against 11% on placebo, and over half of children and adolescents in the flexible-dose trials. then fatigue, headache, abdominal pain, low blood pressure, dizziness, nausea, dry mouth, irritability and nightmares. stopping because of side effects rose from 3% at 1 mg to 18% at 4 mg.
is guanfacine a stimulant or a controlled substance?: no to both. the label calls it a central alpha-2a adrenergic receptor agonist, the same receptor family as some blood-pressure drugs, and says it is not a controlled substance and has no known potential for abuse or dependence. that is why its warnings are about blood pressure, heart rate and sleepiness rather than misuse.

sources for this section

the library rows link to our one-page summary of each study, with the original paper, its funding and our evidence grade on that page.

How long the guanfacine trials actually ran

We could not establish a longest trial length for guanfacine. That is a gap in what we can show you — not evidence that the trials ran long.

The label carries a clinical studies section describing the trials the approval rested on.

The gap between how long the trials ran and how long people actually take these medications is the single most important thing on this page. It is not evidence that longer use is unsafe or ineffective. It is evidence that longer use was not what got tested.

People often stay on these drugs for far longer than the trials ran. The trials behind the approval ran 5 to 8 weeks.

That does not mean longer use is unsafe. It does not mean the drug stops working either. It means longer use was never the thing that got tested.

If you have been on it a long time, that is a fair thing to ask your prescriber about.

No boxed warning on the guanfacine label

The FDA label we quote for guanfacine carries no boxed warning. A boxed warning is the strongest warning the FDA can put on a label, and this label does not have one. That is a fact about the label. It is not a rating of how safe the drug is, and it does not mean the label warns about nothing: what it does warn about is in the sections below.

FDA label effective August 3, 2026. Read the full label on DailyMed

What guanfacine is FDA approved for, and the trials behind it

Approved for the treatment of attention deficit hyperactivity disorder (ADHD) in children and adolescents 6 to 17, as monotherapy and as adjunctive therapy to stimulant medications in 2009, under application NDA 022037. Source: FDA Drugs@FDA.

The label presents all seven trials together and does not say which of them supported the original 2009 approval and which supported later supplements, such as the adjunctive-therapy indication.

Two double-blind, placebo-controlled, fixed-dose monotherapy trials in children and adolescents aged 6 to 17 evaluated once-daily doses of 1 mg to 4 mg for 5 weeks (n=345) and 6 weeks (n=324); every randomized dose group was statistically superior to placebo on the ADHD Rating Scale. The label also describes three flexible-dose monotherapy trials, an 8-week adjunctive trial with psychostimulants (n=455), and a long-term placebo-controlled maintenance trial.

One gap first. The label presents all seven trials together. It does not say which of them backed the first 2009 approval. Nor does it say which backed later additions, such as the use alongside stimulants.

The FDA approved guanfacine in 2009. The approved use was attention deficit hyperactivity disorder (ADHD). It covers children and teens aged 6 to 17. It covers use on its own and use alongside stimulant medicines. The file number is NDA 022037. The source is Drugs@FDA, the FDA's own database.

Two trials tested set doses of 1 mg to 4 mg once a day against a placebo. Everyone was a child or teen aged 6 to 17. Nobody knew who got the drug (double-blind).

One ran 5 weeks with 345 patients. The other ran 6 weeks with 324. Every dose group did better than the placebo on an ADHD rating scale.

The label also describes three trials where the dose could move. It describes an 8-week trial of the drug added to a stimulant in 455 patients. And it describes a longer trial against a placebo on staying well.

Trials: 7 placebo-controlled trials
Duration: 5 to 8 weeks
Participants: 345 and 324 in the fixed-dose trials
Compared against: Placebo

Study 1 (301 study) was a double-blind, placebo-controlled, parallel-group, fixed-dose study, in which efficacy of once daily dosing with guanfacine extended-release tablets (2 mg, 3 mg and 4 mg) was evaluated for 5 weeks (n=345) in children and adolescents aged 6-17 years. Study 2 (304 study) was a double-blind, placebo-controlled, parallel-group, fixed-dose study, in which efficacy of once daily dosing with guanfacine extended-release tablets (1 mg, 2 mg, 3 mg and 4 mg) was evaluated for 6 weeks (n=324) in children and adolescents aged 6-17 years.

Verbatim from the guanfacine FDA label, Clinical Studies section, effective August 3, 2026 — read the full label on DailyMed.

Side effects of guanfacine in the approval trials

Incidence among 513 children and adolescents on guanfacine extended-release (all doses, 1 mg to 4 mg) versus 149 on placebo in the two fixed-dose monotherapy trials. The label cautions that trial rates cannot be directly compared with trials of other drugs and may not reflect rates observed in practice.

Read the limits first. These numbers come from the two set-dose trials in children and teens. 513 of them took the slow-release form at 1 mg to 4 mg. 149 took a placebo.

The label warns that you cannot line these rates up against another drug’s trials. It warns that real life may not match them either.

Somnolence (38% vs 11% on placebo)
Headache (23% vs 19%)
Fatigue (14% vs 3%)
Abdominal pain (11% vs 9%)
Hypotension (7% vs 3%)
Dizziness (6% vs 4%)
Lethargy (6% vs 3%)
Nausea (6% vs 2%)
Decreased appetite (6% vs 4%)
Irritability (6% vs 4%)
Dry mouth (4% vs 1%)

Most common adverse reactions (≥5% and at least twice placebo rate) in fixed-dose monotherapy ADHD trials in children and adolescents (6 to 17 years): hypotension, somnolence, fatigue, nausea, and lethargy

From the guanfacine FDA label, Adverse Reactions section, effective August 3, 2026 — DailyMed.

More from the guanfacine label: drug abuse and dependence

Not a controlled substance
Guanfacine extended-release is not a controlled substance and, per the label, has no known potential for abuse or dependence.
FDA label, Drug Abuse and Dependence section.
Rebound hypertension on abrupt discontinuation
Abrupt discontinuation can lead to clinically significant and persistent rebound hypertension, and hypertensive encephalopathy has also been reported. To minimize this risk, the label directs tapering the total daily dose in decrements of no more than 1 mg every 3 to 7 days.
FDA label, Warnings and Precautions section.

How many Americans take guanfacine

Survey-based federal estimates, published with a lag of about two years. They count prescriptions filled, not outcomes.

These are federal survey numbers. They come out about two years late. They count prescriptions filled. They do not tell you if the drug helped.

The latest year shown is 2019: only 6 survey respondents reported it in 2024, under the 60 AHRQ requires.

4,608,026
prescriptions in the United States (2019), refills included: 690,785
people filling them (2019), ± 243,818 (95%)

The yearly series runs from 2014 to 2019; later years do not meet AHRQ’s reliability rule, so we do not say where it went after that. Whatever you decide about guanfacine, you are deciding alongside about 690,785 other people in 2019.

Prescriptions by year: 2014 2,630,263 · 2017 5,451,594 · 2018 5,429,776 · 2019 4,608,026. Years not shown, under AHRQ’s reliability rule: 2015, 2016, 2020, 2021, 2022, 2023, 2024 (fewer than 60 survey respondents).

Prescriptions are not clearly up or down since 2014. About 691 thousand people in the United States took it in 2019.

Correction (29 September 2026). An earlier version of this section took its numbers from ClinCalc DrugStats, a third-party site that republishes this survey; we now compute them from AHRQ’s public-use files ourselves. It showed 128,407 people and 826,201 prescriptions for 2024, a year that does not meet AHRQ’s reliability rule; the latest year that does is 2019. It said prescriptions were down 69% since 2014; the series stops in 2019 because later years fail the rule, so we state no direction.

Source: AHRQ Medical Expenditure Panel Survey (MEPS), Prescribed Medicines public-use files, 2014 (HC-168A) through 2024 (HC-254A), computed by veisund. People with at least one purchase where the Multum generic name (RXDRGNAM) equals the drug, weighted by the year’s person weight; purchases include refills. Standard errors by Taylor linearization on VARSTR/VARPSU. AHRQ’s reliability rule: a year is not shown when fewer than 60 survey respondents reported the drug or the relative standard error is over 50%. AHRQ cautions that its 2018 questionnaire redesign and the 2020–2022 pandemic years make year-to-year comparisons less certain.

What people report to the FDA about guanfacine

Read this before the numbers.

Anyone can file an adverse event report — patients, doctors, manufacturers — and nobody verifies that the drug caused what was reported. There is no denominator: tens of millions of prescriptions generate reports at an unknowable rate, and reporting rises with news coverage, not necessarily with harm. Counts below are report volumes, not rates, and cannot be compared between drugs. The FDA itself says not to use this data to make medical decisions — we show it because you deserve to see what is in the public record, with its limits stated plainly.

Read this before the numbers.

Anyone can send a report to the FDA. Patients can. Doctors can. Drug makers can. Nobody checks that the drug caused what the report describes.

There is also no bottom number. Tens of millions of prescriptions turn into reports at a rate nobody knows. Reports go up when a drug is in the news, and that is not the same as more harm.

So these are counts of reports. They are not rates. You cannot use them to compare one drug with another. The FDA itself says not to use this data to make medical choices.

We show it because it is on the public record, and you should get to see it with its limits named.

7,823
reports mentioning guanfacine, all time: 4,622
filed as serious (a report-level flag covering every drug and outcome in the report) filed as serious. That flag covers the whole report, and one report can name more than one drug and more than one outcome.

Most-reported reactions

Drug ineffective813
Off label use630
Somnolence471
Aggression388
Fatigue351
Hypotension299
Dizziness291
Insomnia288
Headache283
Bradycardia271

“Drug ineffective” ranking this high is worth noticing: a report of not being helped counts as an adverse event too, and people file them in large numbers.

It is worth noticing how high “drug ineffective” ranks. A report that the drug did not help counts as an adverse event too. People file a lot of them.

Source: FDA Adverse Event Reporting System (FAERS), via openFDA, openFDA dataset refreshed 2026-07-30 (the refresh date of the query endpoint, not the date reports run through).

Drug interactions listed on the guanfacine label

The FDA label’s interactions section, verbatim. A pharmacist checking your actual medication list beats any published list — including this one.

Below is the part of the FDA label that lists other drugs. It is copied word for word.

No list on the web can see what else you take. A pharmacist can. Ask one to check your full list.

Read the label’s interactions section

7 DRUG INTERACTIONS Table 14 contains clinically important drug interactions with guanfacine extended-release tablets [see Clinical Pharmacology ( 12.3 )]. Table 14: Clinically Important Drug Interaction: Effect of other Drugs on Guanfacine Extended-Release Tablets Concomitant Drug Name or Drug Class Clinical Rationale and Magnitude of Drug Interaction Clinical Recommendation Strong and moderate CYP3A4 inhibitors, e.g., ketoconazole, fluconazole Guanfacine is primarily metabolized by CYP3A4 and its plasma concentrations can be significantly affected resulting in an increase in exposure Consider dose reduction [see Dosage and administration ( 2.7 )] Strong and moderate CYP3A4 inducers, e.g., rifampin, efavirenz Guanfacine is primarily metabolized by CYP3A4 and its plasma concentrations can be significantly affected resulting in a decrease in exposure Consider dose increase [see Dosage and administration ( 2.7 )] Strong and moderate CYP3A4 inhibitors increase guanfacine exposure. Decrease guanfacine extended-release tablets to 50% of target dosage when coadministered with strong and moderate CYP3A4 inhibitors ( 2.7 ). Strong and moderate CYP3A4 inducers decrease guanfacine exposure. Based on patient response, consider titrating guanfacine extended-release tablets dosage up to double the target dosage over 1 to 2 weeks ( 2.7 ).

FDA label for guanfacine, effective August 3, 2026 — DailyMed.

Label history: when this label changes, it is recorded in What changed.

Who pays for guanfacine

Two claims datasets and one survey, covering different populations with different instruments — they cannot be reconciled by arithmetic, and where their sum crowds the all-payer estimate, that is a finding about the estimates rather than a percentage.

Medicare Part D · claims · 2024Medicaid · claims floor · 2024Commercially insured adults · not publishedChildren · no per-drug data

Medicare Part D: Read the under-65 group correctly before the numbers: Medicare before 65 means the disabled and dual-eligible population — among the sickest, highest-need people in the program — and reading their utilization as typical adult use would be a category error. The beneficiary total sums brand-level rows, so treat it as an upper bound on distinct people. 46,955 beneficiaries filled 252,004 claims in 2024 — 16,545 aged 65 and over, and 30,410 under 65.
Medicaid: At least 3,999,736 prescriptions in 2024 — a floor, because 51 of 485 national data rows are suppressed for privacy and contribute zero. Medicaid covers more children than any insurer in the country and publishes no age split — how much of this number is pediatric use is not knowable from public data.
All payers (survey estimate): No figure. In AHRQ’s MEPS 2024 Prescribed Medicines file, only 6 survey respondents reported it, under the 60 AHRQ requires before it publishes an estimate, so we do not print one.
The population nobody counts: The commercially insured working-age adult — statistically, the likeliest person to be reading this page — is the one population with no public per-drug count anywhere. Private claims data exists and is sold, but nothing a patient can check is published. For children the record is thinner still: no public source counts pediatric use of guanfacine specifically; the closest the public record comes is condition-level treatment rates for children, which we have traced for one condition in how childhood ADHD got counted.

Sources: Medicare Part D Prescribers — by Geography and Drug, data.cms.gov, National rows, data year 2024 (published with ~17-month lag). Medicaid State Drug Utilization Data 2024, data.medicaid.gov, national aggregate rows. Retrieved 2026-09-01.

Who has been paying for guanfacine, 2019–2024

Medicare Part D

Claims, all ages — the one payer with a public per-drug series.

20192024

140,563 → 252,004 claims

Medicare under 65

Beneficiaries, not ordinary working-age adults: Medicare before 65 means the disabled and dual-eligible population. A gap is a suppressed split, not zero.

20192024

Not published for these years.

Medicaid

A floor each year — small-cell rows are suppressed federally and excluded from the sum.

20192024

3,432,227 → 3,999,736 prescriptions (floor)

Commercially insured adults

No public dataset publishes per-drug commercial claims for any year — the absence is the finding, and it is rendered, not interpolated. The population this library most wants to inform is the one with no public per-drug series, in any year — insurers and PBMs hold that data privately. What the federal surveys do measure — how many adults take these medications at all — is on the adult-usage page.

Sources: Medicare Part D Prescribers by Geography and Drug (data.cms.gov, national rows, per data year); Medicaid State Drug Utilization Data (data.medicaid.gov, national rows). Claims, fills and beneficiaries are different units — compare each series only with itself.

The guanfacine approval, step by step

Step 1
What the approval was actually based on
Which studies did the FDA rely on, how long did they run, and who was in them?
Efficacy of INTUNIV in the treatment of ADHD was established in children and adolescents (6 to 17 years) in: Five short-term, placebo-controlled monotherapy trials (Studies 1, 2, 4, 5, and 6). One short-term, placebo-controlled adjunctive trial with psychostimulants (Study 3). One long-term, placebo-controlled monotherapy maintenance trial (Study 7).
FDA-approved labelling, 14 CLINICAL STUDIES — read the label on DailyMed
Our reading
This entry is anchored on the extended-release product approved for ADHD in 2009 — not on immediate-release guanfacine, which is a 1986 blood-pressure drug under a different application. The same molecule, two different approvals, and only this one was ever tested for ADHD. The trial package is genuinely broader than most here: five monotherapy trials, an adjunctive trial, and a maintenance trial. The population is the catch — children and adolescents only. Adult ADHD use of guanfacine rides on extrapolation, not on this label.
Step 2
The approval
When was it approved, under what application, and by whose review?
Approved
September 2, 2009
Application
NDA022037
Review
STANDARD
Original sponsor
Shire (now Takeda)
Holds it now
Takeda Pharmaceuticals USA
Label submissions since
12
Source: openFDA Drugs@FDA, original application ORIG-1
Step 3
What was added after it was on the market
Which warnings arrived only after millions of people were already taking it?
We have not recorded a post-approval change to the guanfacine label. That is the state of our record, not a finding that nothing was ever added.
Step 4
What independent research has found since
What has been learned by people who were not selling it?
We have not yet added independent post-approval research on guanfacine to the evidence library. Absence here means we have not covered it, not that none exists.
Step 5
What still is not known
Which questions you might reasonably have has nobody answered yet?
- Approved for ages 6 to 17. If the patient is 35, what evidence is the prescription resting on?
- Immediate-release guanfacine was never approved for ADHD. Which version is being prescribed, and does the prescriber know the difference?
- The maintenance trial is the strongest long-term evidence in the ADHD entries here — worth actually reading before assuming the others match it.

Deciding about guanfacine?

Side-effect rates from guanfacine's own label — drug vs placebo, with every caveat the label attaches
How long every medication's approval trials ran — guanfacine beside every other drug in the library, from the same FDA record
12 questions to ask before starting a psychiatric medication — each with the study behind it
Already on it? The 10-question annual review — including the honest case for staying
How long every drug here was tested before approval — one chart, all medications

Open guanfacine (Intuniv) in veisund

The app has the full approval journey, the resources behind it, and people working through the same questions.

Browse the evidence library

guanfacine (Intuniv)

Before you stop or change your guanfacine dose

what the guanfacine warnings mean

no boxed warning, and what the label warns about instead

what the label says about stopping

what the trials measured, in whom, and for how long

side effects, with the label’s numbers

what the research says, in both directions

questions to ask your prescriber about guanfacine

questions people ask

sources for this section

How long the guanfacine trials actually ran

No boxed warning on the guanfacine label

What guanfacine is FDA approved for, and the trials behind it

Side effects of guanfacine in the approval trials

More from the guanfacine label: drug abuse and dependence

Not a controlled substance

Rebound hypertension on abrupt discontinuation

How many Americans take guanfacine

What people report to the FDA about guanfacine

Most-reported reactions

Drug interactions listed on the guanfacine label

Who pays for guanfacine

Who has been paying for guanfacine, 2019–2024

The guanfacine approval, step by step

What the approval was actually based on

The approval

What was added after it was on the market

What independent research has found since

What still is not known

Deciding about guanfacine?

Open guanfacine (Intuniv) in veisund