The guanfacine extended-release label: no boxed warning, but stopping suddenly can spike blood pressure
Intuniv is approved for ADHD, alone or with a stimulant, and has no boxed warning. Its label warns that abrupt discontinuation can cause rebound hypertension, and says to taper by no more than 1 mg every 3 to 7 days.
Reasonable evidence with real limitations. how we score evidence
Caveat on this rating: Rebound cases are postmarketing reports without a rate; trials were in children and adolescents only.
The FDA-approved label for guanfacine extended-release (Intuniv), read for its two most practical warnings: sleepiness and stopping.
Significant findings
INTUNIV "is indicated for the treatment of Attention Deficit Hyperactivity Disorder (ADHD) as monotherapy and as adjunctive therapy to stimulant medications." Its trials were in children and adolescents aged 6 to 17; safety and efficacy below age 6 and in geriatric patients "have not been established". The label carries no boxed warning.
Warning 5.4, Rebound Hypertension: "In post marketing experience, abrupt discontinuation of INTUNIV 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". The label notes children often have stomach illnesses that stop them taking doses, "so they may be especially at risk". Section 2.5: "Patients/caregivers should be instructed not to discontinue INTUNIV without consulting their health care provider... Taper the daily dose in decrements of no more than 1 mg every 3 to 7 days to minimize the risk of rebound hypertension."
Other warnings: dose-dependent drops in blood pressure and heart rate, with fainting reported (5.1); sedation and somnolence (5.2). In the fixed-dose trials somnolence was reported by 38 percent on any dose against 11 percent on placebo, rising from 28 percent at 1 mg to 51 percent at 4 mg. It is not interchangeable mg for mg with immediate-release guanfacine (2.3).
The other direction
The label states efficacy from five controlled monotherapy trials, a randomised withdrawal study and an adjunctive trial with stimulants. Its blood pressure and heart rate drops "were less pronounced over time of treatment." The rebound cases involved high doses stopped abruptly, often alongside stimulants.
What this does not show
It does not tell anyone to stop or change a dose; the label's own instruction is not to stop without the prescriber.
Worth asking
If a dose is missed for a few days because of a stomach bug, what should we do when restarting?
Source
INTUNIV (guanfacine) extended-release tablets: FDA-approved prescribing information, Dosage 2.3 and 2.5, Warnings and Precautions 5.1 to 5.4, Adverse Reactions 6.1 — Takeda Pharmaceuticals America, Inc.; US Food and Drug Administration (2025)
Regulator or national health body
How this was scored
- Study design
- Regulatory safety determination
- Funding
- Industry funded
- Published in
- Regulator or national health body
- Sample size
- not recorded
- Preregistered
- not recorded
- Conflicts disclosed
- not recorded
- Independent of proponent
- not recorded
- Retracted
- No
Read the full scoring rubric, including what it can't tell you.
Published October 21, 2026.
Questions
How strong is the evidence behind this?
veisund rates this source "moderate evidence". Reasonable evidence with real limitations. It scores 57 out of 100 on our published rubric. One caveat travels with that badge: Rebound cases are postmarketing reports without a rate; trials were in children and adolescents only. The score is calculated from recorded facts about the source — study design, funding, publication venue, sample size, preregistration — not typed in by an editor.
What is the source for this?
INTUNIV (guanfacine) extended-release tablets: FDA-approved prescribing information, Dosage 2.3 and 2.5, Warnings and Precautions 5.1 to 5.4, Adverse Reactions 6.1 — Takeda Pharmaceuticals America, Inc.; US Food and Drug Administration (2025). Published in: Regulator or national health body. The full source is linked on this page so you can read it yourself.
Who paid for this research, and does that matter?
Study design: Regulatory safety determination. Funding: Industry funded. Independence from the proponent is not recorded. Industry sponsorship is one of the most reliably measured biases in medicine, which is why funding carries real weight in the score rather than sitting in a footnote.
Is guanfacine (Intuniv, Tenex), intuniv FDA approved?
Yes — this medication carries FDA approval. Approval is always for a specific indication, not for every use it is prescribed for.
Is this medical advice?
This is information to bring to your prescriber, not medical advice and not a reason to change anything on your own. Nothing here is an instruction to stop or reduce a medication. If you are in crisis, call or text 988.
This is information to bring to your prescriber, not medical advice and not a reason to change anything on your own. Nothing here is an instruction to stop or reduce a medication. If you are in crisis, call or text 988.