Non-Stimulant ADHD Medications: All 4 FDA Options Compared

When people hear "ADHD medication," they usually picture a stimulant: Adderall, Ritalin, Vyvanse, Concerta. Stimulants are the most used and the most studied. They are not the only option, though, and for some people they are not the right one.

This guide covers the four non-stimulant medications the US Food and Drug Administration (FDA) has approved for ADHD, what each one does, who it is approved for, and when doctors tend to consider them.

A note on where this comes from. I live in Turkey, where the medication lineup is not the same as in the US. I am not a doctor, and this is a research-based explainer built from the current FDA labels on DailyMed and from peer-reviewed reviews. Which medication fits you, and at what dose, is a decision you make with your prescriber.

What "non-stimulant" actually means

Stimulants for ADHD come in two families: methylphenidate (Ritalin, Concerta, Focalin) and amphetamines (Adderall, Vyvanse). They raise the activity of dopamine and norepinephrine in the brain fairly quickly. If you want the stimulant side in more detail, there is a separate explainer on what Adderall is.

Non-stimulants work through other routes. Two of them, atomoxetine and viloxazine, act mainly on norepinephrine. The other two, guanfacine and clonidine, act on alpha-2 receptors, which are part of the system that regulates attention, arousal and impulse control.

Two practical differences follow from this:

• None of the four is a controlled substance. The Strattera label states that atomoxetine is not controlled, the Qelbree label lists no DEA schedule, and the Intuniv label says guanfacine ER has no known potential for abuse or dependence. Stimulants, by contrast, are Schedule II drugs with strict refill rules.
• They build up gradually. A stimulant can be judged within days. A non-stimulant usually needs weeks.

The four FDA-approved non-stimulants at a glance

Medication	Brand name	Type	FDA-approved ages	Approved as add-on to a stimulant?	Common side effects on the label
Atomoxetine	Strattera (generics available)	Norepinephrine reuptake inhibitor	6 and older, including adults	No	Children: nausea, vomiting, tiredness, decreased appetite, stomach pain, sleepiness. Adults: constipation, dry mouth, nausea, decreased appetite, dizziness, erectile dysfunction, trouble urinating
Viloxazine ER	Qelbree	Norepinephrine reuptake inhibitor	6 and older, including adults	No	Sleepiness, decreased appetite, tiredness, nausea, insomnia, headache; in adults also dry mouth and constipation
Guanfacine ER	Intuniv (generics available)	Alpha-2A agonist	Studied and established in ages 6 to 17	Yes	Low blood pressure, sleepiness, tiredness, nausea, lethargy
Clonidine ER	Generic tablets; Onyda XR oral suspension	Alpha-2 agonist	6 to 17 (tablets); 6 and older (Onyda XR)	Yes	Sleepiness, tiredness, irritability, nightmares, insomnia, constipation, dry mouth

The age ranges and side effects come from the current DailyMed labels, which I checked on October 23, 2026. The brand Kapvay, the original clonidine ER tablet for ADHD, is listed as discontinued in the FDA's Drugs@FDA database, but generic clonidine ER tablets with the same ADHD indication are still on DailyMed. Viloxazine was available only as brand-name Qelbree on that date.

Atomoxetine (Strattera)

Atomoxetine was first approved in the US in 2002, which makes it the longest-standing of the four as an ADHD treatment. It is approved for ADHD in adults and in children 6 and older.

What to know from the label:

• The capsules are swallowed whole and are not opened.
• It carries a boxed warning about suicidal thoughts and behaviors in children and teens, so close monitoring is expected, especially early in treatment and after dose changes.
• It can rarely cause liver injury. The label says it should be stopped and not restarted if there is jaundice or lab evidence of liver injury.
• Heart rate and blood pressure are checked at the start, after dose increases, and periodically.
• People who are "CYP2D6 poor metabolizers" break the drug down more slowly and end up with higher levels in the blood, which matters for dosing.
• When it is stopped, the label says no taper is needed.

On timing, a review of atomoxetine data found that some effect can appear within one to two weeks, but the response can keep growing for up to 24 weeks or longer (Clemow and Bushe, 2015). The authors worked for the manufacturer, which is worth keeping in mind. In practice the finding means a trial that is judged after ten days may be judged too soon.

There is a longer, dedicated piece on Strattera and atomoxetine in this series.

Viloxazine ER (Qelbree)

Viloxazine ER was approved in the US in 2021, and its label now covers adults and children 6 and older. It is the newest of the four.

What sets it apart on the label:

• Drug interactions. Viloxazine strongly affects an enzyme called CYP1A2. It must not be combined with certain medications that this enzyme breaks down, and it is not used with MAO inhibitors or within 14 days of stopping one. This makes a full medication list especially important.
• Boxed warning. Like atomoxetine, it has a boxed warning about suicidal thoughts and behaviors.
• Bipolar screening. The label notes that drugs acting on norepinephrine can trigger a manic or mixed episode in people with bipolar disorder, so screening comes before starting.
• Sleepiness. It can cause somnolence and fatigue, which is a little unexpected for an ADHD medication.
• Easier to take for some. The capsule can be opened and sprinkled on applesauce or pudding, which helps people who cannot swallow capsules.

In adults, the evidence is thinner than for atomoxetine. A 2023 meta-analysis found viloxazine ER more effective than placebo, but only one adult trial was available at the time (Radonjić et al., 2023).

Guanfacine ER (Intuniv)

Guanfacine ER is approved for ADHD on its own and as an add-on to stimulant medication. Its trials were done in children and teens aged 6 to 17, and the label says safety and efficacy below age 6 have not been established. It is not FDA-approved for adults, so adult use is off-label. That said, the 2023 adult meta-analysis found guanfacine more effective than placebo across two adult trials (Radonjić et al., 2023).

What to know from the label:

• Blood pressure and heart rate drop. This is the main safety point. Dizziness, fainting and very slow heart rate are listed risks.
• No sudden stops. The label warns that abrupt discontinuation can cause rebound high blood pressure, so the dose is tapered down.
• Swallow whole. Crushing, chewing or breaking the tablet speeds up the release.
• Avoid high-fat meals with the dose, because they increase how much of the drug is absorbed.
• Not interchangeable with regular guanfacine. The immediate-release guanfacine sold for blood pressure cannot be swapped milligram for milligram.

Sleepiness is common, especially at the start. For some people this is a drawback. For others, whose evenings are the hardest part of the day, it is part of why a prescriber suggests it.

Clonidine ER (Kapvay generics and Onyda XR)

Clonidine was first approved in the US in 1974, originally as a blood pressure medication. The extended-release versions are approved for ADHD alone or alongside a stimulant.

There are two forms right now:

• Extended-release tablets (the generic successors to Kapvay), established in ages 6 to 17 and taken twice a day, with an equal or larger dose at bedtime.
• Onyda XR, an extended-release liquid, approved for children 6 and older and taken once a day at bedtime.

The safety picture is close to guanfacine's: lower blood pressure and heart rate, sleepiness, and rebound high blood pressure if stopped abruptly. Neither form can be substituted milligram for milligram with other clonidine products. As an add-on to a stimulant, the most common side effects on the label are sleepiness, tiredness, decreased appetite and dizziness.

How non-stimulants compare with stimulants

On average, stimulants have the larger effect. The American Academy of Pediatrics (AAP) guideline ranks the strength of evidence for school-age children as stimulants first, then atomoxetine, guanfacine ER and clonidine ER. It cites an average effect size of about 1.0 for stimulants and about 0.7 for non-stimulants, and calls the evidence for non-stimulants "sufficient, but less strong" (Wolraich et al., 2019). Viloxazine was approved after that guideline was written.

In adults, the meta-analysis by Radonjić and colleagues found atomoxetine, guanfacine and viloxazine ER all more effective than placebo, while placebo was better tolerated (Radonjić et al., 2023).

An average effect size is a statement about groups. It does not tell you how you will respond. Some people get a clear benefit from a non-stimulant after a stimulant did little, and the reverse also happens. If a first medication fails, it does not mean medication as a whole has failed; I wrote more about this in when ADHD medication is not working.

When non-stimulants are usually considered

A 2022 clinical review summarizes the main situations: when stimulants did not work well enough or could not be tolerated, when certain co-occurring conditions are present, or when the patient simply prefers a non-stimulant (Newcorn et al., 2022). In everyday terms, that can look like:

• Side effects that did not settle. Appetite loss, insomnia, a racing heart or a rise in anxiety on stimulants. There is a separate guide on ADHD medication and anxiety.
• Concerns about misuse. A personal or family history of substance use, or a household where a controlled medication could be diverted. Whether stimulants themselves are addictive at prescribed doses is a separate question, covered in is ADHD medication addictive.
• Heart or blood pressure questions. These need a careful look with any ADHD medication, stimulant or not. The guanfacine and clonidine labels lower blood pressure, while the atomoxetine and viloxazine labels ask for monitoring of rises in heart rate and blood pressure. My piece on ADHD medication, heart and blood pressure goes into this.
• Coverage through the whole day. The atomoxetine review cited above found that a single daily dose can provide a 24-hour effect, which can cover early mornings and evenings, the hours when a stimulant has worn off or has not started yet.
• Adding to a stimulant. Guanfacine ER and clonidine ER are FDA-approved add-ons when a stimulant helps but not enough.

Off-label options

Doctors sometimes prescribe medications that are not FDA-approved for ADHD. Bupropion, an antidepressant, is one example. "Off-label" is legal and common, but it means the drug's label was not built around ADHD trials, so the decision leans more heavily on the prescriber's judgment.

For a full map of every option, stimulant and non-stimulant, see the list of ADHD medications. And if you are weighing pills against other approaches, there is a guide on ADHD treatment without medication.

What to expect if you start one

A non-stimulant trial asks for patience in a way a stimulant trial does not. Doses are usually raised in steps over several weeks, and the benefit tends to come in slowly instead of switching on. That slow start is hard on an ADHD brain that wants proof by Friday.

Two things make a trial easier to judge. First, agree with your prescriber on how long the trial should last before anyone decides it failed. Second, keep a simple weekly note: sleep, appetite, mood, and the two or three situations that bothered you most before you started. Memory is a weak instrument for slow changes.

If cost is part of the picture, generic atomoxetine, guanfacine ER and clonidine ER exist, while Qelbree is brand only. Prices change often, so it is worth asking the pharmacy about the generic before you fill the prescription.

And one calm reminder: starting, changing or stopping any of these medications is a decision for you and the person who prescribes them, not for an article.