Qelbree vs Strattera: Non-Stimulant ADHD Medications Compared

Qelbree (viloxazine) and Strattera (atomoxetine) are both non-stimulant ADHD medications that work on norepinephrine, and both are FDA-approved for adults and children 6 and older. Strattera has been on the market since 2002; Qelbree was approved for children in 2021 and for adults in 2022. Both carry a boxed warning about suicidal thoughts and behaviors, and both take longer than stimulants to judge.

The biggest practical differences are in drug interactions and metabolism. Atomoxetine is broken down by the liver enzyme CYP2D6, so genetics and some antidepressants can raise its levels several-fold, while viloxazine strongly blocks a different enzyme, CYP1A2, which rules out several common medications. Your current medications often decide between them before anything else does. The choice belongs with your prescriber.

Side-by-side comparison

How they work and how long they take

Both labels describe the drug as a selective norepinephrine reuptake inhibitor. Unlike stimulants, they are not judged dose by dose, and their benefit is assessed over weeks.

The labels show the slower pace. Qelbree's doses are raised at weekly intervals, and its pediatric trials ran 6 to 8 weeks. Strattera's label allows the target dose to be reached after a minimum of 3 days, but says that if response is not optimal, the dose may be raised to the maximum only after 2 to 4 additional weeks at the target dose. NICE's ADHD guideline uses 6-week trials when judging whether a medication has helped enough. In practice, expect several weeks before you and your prescriber can tell whether either one is working.

How much benefit to expect is harder to say. The 2018 network meta-analysis in Lancet Psychiatry found atomoxetine better than placebo in both children and adults, with smaller average effects than stimulants. Viloxazine was not included, because it was approved after that analysis. The AAP's 2019 guideline puts the average effect size at about 0.7 for non-stimulants versus about 1.0 for stimulants, and rates the evidence for atomoxetine, then extended-release guanfacine, then extended-release clonidine as sufficient but less strong than for stimulants. Neither label reports a head-to-head trial against the other drug.

Interactions: often the deciding factor

Qelbree and CYP1A2

Viloxazine is a strong inhibitor of CYP1A2, a liver enzyme that clears several common drugs. Its label makes it contraindicated with sensitive CYP1A2 substrates or those with a narrow therapeutic range; the Medication Guide names alosetron, duloxetine, ramelteon, tasimelteon, tizanidine and theophylline. Moderately sensitive CYP1A2 substrates are not recommended with it, and viloxazine also weakly inhibits CYP2D6 and CYP3A4, so doses of other drugs may need adjusting. If you take duloxetine for depression or pain, or tizanidine for muscle spasm, Qelbree is ruled out unless that medication changes.

Strattera and CYP2D6

Atomoxetine is cleared mainly through CYP2D6, an enzyme whose activity varies with genetics. The label estimates that about 7% of White people, 2% of Asian people and 2% of Black or African American people are CYP2D6 poor metabolizers. In poor metabolizers, atomoxetine's half-life is about 21.6 hours compared with 5.2 hours in others, and heart rate rises more on average.

Some antidepressants have the same effect. In the label's studies, paroxetine raised atomoxetine exposure 6.5-fold and fluoxetine 6- to 8-fold in people who were not poor metabolizers. For people taking a strong CYP2D6 inhibitor or known to be poor metabolizers, the label recommends a longer titration interval and says to consider genetic testing to determine metabolizer status. That matters because ADHD and depression often occur together; see ADHD and depression: what comes first.

Both

Both labels make use with a monoamine oxidase inhibitor (MAOI), or within 14 days of stopping one, contraindicated. Bring a full medication list, including supplements, to the visit; the checklist in how to prepare your medication history helps.

The boxed warnings and other safety issues

Both boxed warnings concern suicidal thinking, but they are worded differently. Strattera's warns that it increased the risk of suicidal ideation in children 6 and older in short-term studies and calls for close monitoring, especially in the first months and after dose changes. Qelbree's states that higher rates of suicidal thoughts and behavior were reported with Qelbree than with placebo in clinical studies, and calls for close monitoring of all patients. Qelbree's label also notes higher rates of insomnia and irritability, and lists symptoms such as anxiety, agitation, panic attacks and impulsivity as possible early warning signs.

If you are thinking about suicide or are in crisis, call or text 988 (the 988 Suicide & Crisis Lifeline) or go to the nearest emergency room. Families of children starting either drug should agree with the prescriber on what changes to watch for and how to reach the team quickly; a plan like the one in safety planning for suicidal thoughts can help.

Strattera's label says liver injury reported after marketing occurred within 120 days of starting in most cases, and that liver tests should be done at the first sign of liver problems, such as itching, dark urine, yellowing skin or right upper abdominal tenderness. Strattera capsules are an eye irritant and are not meant to be opened.

What the labels say about dosing

Both drugs are started low and raised in steps, but the labels describe the steps differently. The ranges below are what the labels state; your own dose is set by your prescriber, who may move more slowly.

Practical details differ too. Qelbree capsules can be opened and sprinkled on a spoonful of applesauce, to be eaten within 2 hours, or pudding, within 15 minutes, without chewing. Strattera can be taken once in the morning or split into a morning and a late-afternoon dose; the capsules should be swallowed whole.

Stopping

Strattera's label reports no evidence of symptom rebound or a withdrawal syndrome after it was stopped in studies. That does not make stopping a do-it-yourself decision, because ADHD symptoms return and mood needs watching, but it is a real difference from guanfacine and clonidine, which must be tapered. Talk with your prescriber before stopping any of them.

Guanfacine ER and clonidine ER: the other non-stimulants

Two other non-stimulants act on a different target, alpha-2 adrenergic receptors. Extended-release guanfacine (Intuniv) and extended-release clonidine are FDA-approved for ADHD as monotherapy or as add-ons to stimulants, and their effectiveness was established in children and adolescents 6 to 17. Sleepiness is among the most common side effects of both, both can lower blood pressure and heart rate, and both must be tapered when stopped because abrupt discontinuation can cause rebound high blood pressure.

For adults, NICE advises using guanfacine only with advice from a specialist ADHD service, since adult use is off-label. In children, the add-on role is often what makes these drugs useful: the AAP notes that only extended-release guanfacine and clonidine have enough evidence as add-ons to stimulants to have achieved FDA approval for that use. The broader decision is in stimulant vs non-stimulant ADHD medication.

Where non-stimulants fit in the treatment sequence

Guidelines mostly place these drugs after stimulants, with exceptions. NICE recommends atomoxetine for adults who cannot tolerate lisdexamfetamine or methylphenidate, or whose symptoms have not responded to separate 6-week trials of both. For children 5 and older, it lists atomoxetine or guanfacine in the same position. NICE's guideline was last updated in 2019, before viloxazine was approved, so it does not address Qelbree.

A prescriber may consider a non-stimulant earlier when there is a reason to avoid stimulants, such as:

• A personal or household history of stimulant misuse, since neither drug is a Schedule II stimulant.
• Stimulant side effects such as appetite loss, insomnia or anxiety that did not settle.
• Repeated difficulty filling stimulant prescriptions during shortages; see what to do during a stimulant shortage.
• A preference for steady, all-day coverage rather than a dose that wears off.

These are reasons to discuss, not automatic choices. Anxiety alone does not decide it: NICE recommends offering people with ADHD and an anxiety disorder the same medication choices as anyone else with ADHD. See ADHD and anxiety: which to treat first.

What the evidence does not show

• Which of the two works better. Neither label reports a direct comparison, and the 2018 network meta-analysis predates viloxazine's approval.
• Long-term comparative effects. That analysis found too little data to compare ADHD medications at 26 or 52 weeks.
• A genetic test that picks the drug. Strattera's label suggests considering CYP2D6 testing to guide its dosing, but the AAP does not recommend current pharmacogenetic panels for choosing ADHD medication in general, citing insufficient evidence.

Questions to ask your prescriber

1. Do any of my current medications interact with Qelbree (CYP1A2) or Strattera (CYP2D6)?
2. Would genetic testing for CYP2D6 change the plan for Strattera? (Its label says to consider it; see pharmacogenomic testing and its limits.)
3. How long will we wait before deciding whether it works?
4. Which mood or behavior changes should make me call right away?
5. How will we check heart rate and blood pressure?
6. Is pregnancy possible in the next year, and how does that affect the choice?
7. If this does not work, what comes next?

Do not start, stop or switch either medication on your own. Neither should be combined with an MAOI, and stopping guanfacine or clonidine abruptly can be dangerous.

How Dr. Lewis's team approaches non-stimulant options

The practice's ADHD assessment, for children and adults in person or by telehealth, leads to a written summary and treatment plan that may include lifestyle changes, nutrition, psychotherapy, executive-function coaching, and medications when appropriate. Ongoing medication management is part of the practice's care. Details are on the ADHD assessment page and the ADHD psychiatrist page, and other decision guides are in the choosing psychiatric care guide.

Frequently asked questions

Is Qelbree an antidepressant?

In the U.S., Qelbree is FDA-approved only for ADHD, in adults and children 6 and older. Its label carries a boxed warning about suicidal thoughts and behaviors, so mood changes should be reported promptly.

Can I take Qelbree with Cymbalta (duloxetine)?

No. Qelbree's label lists duloxetine among the drugs that are contraindicated with it because viloxazine sharply raises their levels. Talk with your prescriber before changing either medication.

Does Strattera work right away?

No. It builds over weeks, and the label allows the dose to be raised to its maximum only after 2 to 4 more weeks at the target dose if response is not optimal. Missing doses makes it harder to judge.

Can I take either one with a stimulant?

Neither Qelbree nor Strattera is FDA-approved as an add-on to stimulants; combining them would be off-label and a specialist decision. Extended-release guanfacine and clonidine are the non-stimulants approved as add-ons, in children 6 to 17.

Will I feel a crash when it wears off?

Qelbree and Strattera are taken every day and their benefit builds over weeks rather than rising and falling with each dose. Report side effects such as sleepiness, nausea or mood changes to your prescriber.

Which one is safer for my liver?

Strattera has a warning for rare severe liver injury, and its label lowers the dose in moderate or severe liver impairment. Qelbree's label does not list liver injury among its warnings. If you have liver disease, tell your prescriber before either one is chosen.

Sources

1. Qelbree (viloxazine extended-release capsules) prescribing information and Medication Guide. Supernus Pharmaceuticals / DailyMed (NLM), 2025. dailymed.nlm.nih.gov
2. Strattera (atomoxetine) capsules prescribing information. Eli Lilly and Company / DailyMed (NLM), 2026. dailymed.nlm.nih.gov
3. Drugs@FDA: Qelbree (viloxazine hydrochloride), NDA 211964. U.S. Food and Drug Administration, 2022. accessdata.fda.gov
4. Drugs@FDA: Strattera (atomoxetine hydrochloride), NDA 021411. U.S. Food and Drug Administration, 2002. accessdata.fda.gov
5. Intuniv (guanfacine extended-release tablets) prescribing information. Takeda Pharmaceuticals / DailyMed (NLM), 2025. dailymed.nlm.nih.gov
6. Clonidine hydrochloride extended-release tablets prescribing information. Somerset Therapeutics / DailyMed (NLM), 2024. dailymed.nlm.nih.gov
7. Attention deficit hyperactivity disorder: diagnosis and management (NG87), Recommendations. National Institute for Health and Care Excellence, 2019. nice.org.uk
8. Clinical Practice Guideline for the Diagnosis, Evaluation, and Treatment of Attention-Deficit/Hyperactivity Disorder in Children and Adolescents. American Academy of Pediatrics, Pediatrics 144(4):e20192528, 2019. pmc.ncbi.nlm.nih.gov
9. Comparative efficacy and tolerability of medications for attention-deficit hyperactivity disorder in children, adolescents, and adults: a systematic review and network meta-analysis. Lancet Psychiatry 5(9):727-738 (Cortese S et al.), PubMed 30097390, 2018. pubmed.ncbi.nlm.nih.gov

Educational information, not medical, tax or legal advice. Decisions about diagnosis, medication and treatment belong with a clinician who knows your history.