--- title: "SIMTRIYO (Centanafadine) Explained: A Detailed Guide to the New ADHD Medication" slug: simtriyo-centanafadine-adhd-complete-guide-2026 category: health category_label: "Health" author: "BrainWavePost Staff" date: 2026-07-30 tags: ["ADHD", "Simtriyo", "centanafadine", "FDA", "prescribing information", "mental health", "pediatrics", "medication"] read_time_minutes: 14 canonical_url: https://brainwavepost.com/article/simtriyo-centanafadine-adhd-complete-guide-2026 source: BrainWavePost --- # SIMTRIYO (Centanafadine) Explained: A Detailed Guide to the New ADHD Medication *Health · 2026-07-30 · BrainWavePost Staff · 14 min read* > A deep dive into SIMTRIYO (centanafadine) — the first FDA-approved norepinephrine-dopamine-serotonin reuptake inhibitor for ADHD: how it works, the four phase 3 trials, exact dosing by age and weight, the boxed warning, contraindications and what is still unknown. > **How this article is sourced** _(info)_ > > Every factual claim below comes from the FDA-approved SIMTRIYO Full Prescribing Information (revised 7/2026), Otsuka Pharmaceutical's approval announcement, ClinicalTrials.gov registrations, peer-reviewed clinical guidance from the American Academy of Pediatrics, and data from the CDC and NIMH. Numbered citations link to the primary documents at the end. No efficacy or safety figure here is estimated or inferred. [1][2][3][4][5][6][7] In July 2026 the U.S. Food and Drug Administration approved SIMTRIYO® (centanafadine) extended-release capsules for attention-deficit/hyperactivity disorder (ADHD) in adults and pediatric patients 6 years of age and older weighing at least 20 kg. [1][2] It is the first approved medicine in a class its manufacturer calls the norepinephrine-dopamine-serotonin reuptake inhibitors (NDSRIs). [1][3] This guide walks through what the approved label actually says — mechanism, trial data, dosing, warnings and open questions — rather than the marketing summary. ## The headline facts - **≥6 yrs** — approved age, patients ≥20 kg [1][2] - **4** — phase 3 randomised placebo-controlled trials [1][3] - **5.2 h** — mean elimination half-life [2] ## What the drug is — and what it is not Centanafadine has inhibitory activity at the norepinephrine, dopamine and serotonin reuptake transporters. The approved label states plainly that 'the mechanism of action of centanafadine in the treatment of ADHD is unclear; however, its efficacy could be mediated through its activity as a norepinephrine-dopamine-serotonin reuptake inhibitor.' [2] Crucially, the same label classifies centanafadine as a central nervous system (CNS) stimulant, and its controlled-substance schedule is 'to be determined after review by the Drug Enforcement Administration.' [2] Otsuka has said the product will reach pharmacies later in the year, once DEA scheduling is complete. [3] > **A common misreading** _(note)_ > > Early coverage described centanafadine as a 'non-stimulant'. The FDA-approved labeling describes it as a CNS stimulant with a boxed warning for abuse, misuse and addiction, and it awaits DEA scheduling. Readers comparing it to atomoxetine or guanfacine — true non-stimulants — should treat that framing with caution and rely on the label. [2] ## Formulation and pharmacokinetics - Each extended-release capsule contains a combination of immediate-release, extended-release and delayed-release beads, delivering 140 mg, 210 mg or 280 mg of centanafadine (equivalent to 164.4 mg, 246.6 mg or 328.8 mg of centanafadine hydrochloride). [2] - The mean elimination half-life is 5.2 hours and mean apparent clearance is 410 mL/min. [2] - Centanafadine is metabolised primarily by monoamine oxidase A; the most abundant metabolite (a lactam) is not pharmacologically active. [2] - After a radiolabelled dose, 88% of radioactivity was recovered in urine as metabolites and 7% in faeces. [2] ## Exact dosing, by age and body weight SIMTRIYO is taken once daily in the morning, with or without food, at roughly the same time each day. Capsules must not be cut, crushed or chewed; they can be swallowed whole or opened and sprinkled over one tablespoon (15 mL) of applesauce, yogurt or orange juice, then consumed immediately with water and never saved for later. [2] 1. Children 6 to 12 years, weight-based: 20 kg to under 35 kg → 140 mg once daily; 35 kg to 50 kg → 210 mg once daily; greater than 50 kg → 280 mg once daily. [2] 2. Adolescents 13 to 17 years weighing at least 20 kg: 280 mg once daily. [2] 3. Adults: start at 210 mg once daily; may be increased to the maximum 280 mg once daily based on clinical response and tolerability. [2] 4. Missed dose: take it as soon as remembered but no later than 4 hours after the usual dosing time, and never take two doses in one day. [2] The label also records what was not established: the effectiveness of 140 mg once daily in 13–17-year-olds (and its weight-based equivalent in 6–12-year-olds) was not demonstrated, and 210 mg once daily and weight-based equivalents have not been studied in patients aged 6–17 and are not recommended. [2] Anyone switching from a monoamine oxidase inhibitor must wait at least 14 days after stopping the MAOI before starting SIMTRIYO. [2] ## The four phase 3 trials in detail Approval rests on four randomised, double-blind, placebo-controlled studies: one in children (NCT05428033), one in adolescents (NCT05257265) and two in adults (NCT03605680 and NCT03605836). Symptom change was measured with the ADHD Rating Scale-5 (ADHD-RS-5) in the paediatric studies and the ADHD Investigator Symptom Rating Scale (AISRS) in adults. [3][4][8][9][10][11] ### Children, ages 6 to 12 (Study 1, N=480) Centanafadine 280 mg once daily (n=154) versus placebo (n=151) produced a placebo-subtracted difference of −5.6 points on ADHD-RS-5 total score (95% CI −8.78 to −2.33). [4][8] ### Adolescents, ages 13 to 17 (Study 2, N=459) Centanafadine 280 mg once daily (n=149) versus placebo (n=149) produced a placebo-subtracted difference of −4.4 points on ADHD-RS-5 (95% CI −6.83 to −1.87). [4][9] ### Adults (Studies 3 and 4) In Study 3 (N=466, mean age 36) the placebo-subtracted AISRS differences were −3.2 for the low dose (95% CI −5.79 to −0.51) and −2.7 for the high dose (95% CI −5.35 to −0.14). In Study 4 (N=440, mean age 35) they were −4.0 (95% CI −6.55 to −1.46) and −4.4 (95% CI −7.02 to −1.82). [4][10][11] The adult trials used an earlier formulation; regulators concluded no differences in effectiveness are expected between those low- and high-dose formulations and SIMTRIYO 210 mg and 280 mg once daily, respectively. [4] > **How to read these numbers** _(tip)_ > > A placebo-subtracted difference of roughly 3 to 6 points on scales that run to 54 points is a real but moderate average effect, measured at six weeks. Group averages say nothing about how any individual will respond, and none of these trials compared centanafadine head-to-head against an existing stimulant or non-stimulant. [4] ## The boxed warning SIMTRIYO carries a boxed warning — the FDA's most serious labeling requirement — covering two distinct risks. [2] - Suicidal ideation and behaviors in pediatric patients aged 6 years and older: in a 6-week study, higher rates of suicidal ideation and behaviour were reported in centanafadine-treated children aged 6 to 12 than in placebo-treated children. All paediatric patients should be monitored closely for suicidal ideation, clinical worsening or unusual behaviour change, especially in the first months of therapy, and families should be told to report such symptoms immediately. [2] - Abuse, misuse and addiction: as a CNS stimulant, SIMTRIYO exposes patients to risks that can lead to substance use disorder; misuse and abuse can result in overdose and death, with risk increased at higher doses or by non-approved routes such as snorting or injection. Clinicians are directed to assess abuse risk before starting and to reassess it throughout treatment, and to counsel families on safe storage and disposal. [2] ## Contraindications - Known hypersensitivity to centanafadine or any excipient — angioedema and anaphylaxis have been reported. [2] - Current use of, or use within 14 days of stopping, an MAOI, because of the risk of hypertensive crisis and serotonin syndrome. [2] - Pheochromocytoma or a history of pheochromocytoma. [2] ## Warnings, precautions and pre-treatment screening Beyond the boxed warning, the label lists risks to patients with serious cardiac disease, increased blood pressure and heart rate, psychiatric adverse reactions (psychotic or manic symptoms occurred in about 0.1% of CNS-stimulant-treated patients versus 0% on placebo in a pooled analysis), hypersensitivity reactions, long-term suppression of growth in paediatric patients, peripheral vasculopathy including Raynaud's phenomenon, serotonin syndrome, and motor or verbal tics and worsening of Tourette's syndrome. [2][4] Before prescribing, clinicians are instructed to assess the risk of abuse, misuse and addiction; screen for cardiac disease including family history of sudden death or ventricular arrhythmia; check heart rate and blood pressure; evaluate risk factors for a manic episode; and check for a personal or family history of tics or Tourette's syndrome. [2][4] SIMTRIYO is not recommended in severe hepatic impairment, and is not approved or recommended in children under 6 years or under 20 kg — younger children in the programme had a higher incidence of weight loss. [2] ## Adverse reactions reported in trials - Adults: headache, decreased appetite, insomnia, nausea, dry mouth and diarrhoea. [4] - Children and adolescents: rash, decreased appetite, nausea, headache and abdominal pain. [4] ## Where it fits alongside existing ADHD treatment The American Academy of Pediatrics' clinical practice guideline positions FDA-approved medication alongside behaviour therapy and school supports, with the mix depending on the child's age and circumstances. [5] ADHD is common — the CDC reports roughly 7 million U.S. children aged 3–17 have ever been diagnosed, and NIMH estimates about 4.4% of U.S. adults are affected — and response to any single agent varies widely. [6][7] Centanafadine's practical appeal is a distinct triple-monoamine mechanism approved across a wide age range in one product; its practical constraints are a boxed warning, pending DEA scheduling, moderate effect sizes and the absence of head-to-head comparisons with established treatments. [2][4] > The mechanism of action of centanafadine in the treatment of ADHD is unclear; however, its efficacy could be mediated through its activity as a norepinephrine-dopamine-serotonin reuptake inhibitor. > > — SIMTRIYO Full Prescribing Information, Section 12.1 [2] ## What is still unknown - Long-term efficacy and safety beyond the short controlled trials, including growth trajectories in children treated for years. [2] - Comparative effectiveness against methylphenidate, amphetamine, atomoxetine, guanfacine or clonidine — no head-to-head trials support ranking it against these. [2][5] - The final DEA control schedule, which will shape prescribing rules, refill limits and pharmacy handling. [2][3] - Real-world price, insurance coverage and availability, which Otsuka and payers will determine after launch. [3] > **Editorial note — not medical advice** _(note)_ > > This article summarises publicly available regulatory and clinical documents for general education. It is not medical advice, and nothing here should be used to start, stop or change a medication. Discuss ADHD diagnosis and treatment with a qualified clinician, and consult the full prescribing information for complete details. If you or someone you know is having thoughts of suicide, in the U.S. call or text 988 for the Suicide & Crisis Lifeline. ## Sources and further reading - [1] Otsuka Pharmaceutical Co., Ltd. — 'Otsuka Receives FDA Approval for First-in-Class SIMTRIYO® (centanafadine) for the Treatment of Attention-Deficit Hyperactivity Disorder (ADHD) in Adults and Pediatric Patients Aged 6 Years and Older' (July 2026): https://www.otsuka.co.jp/en/company/newsreleases/2026/20260727_1.html - [2] SIMTRIYO® (centanafadine) extended-release capsules — U.S. Full Prescribing Information, Otsuka America Pharmaceutical, Inc. (revised 7/2026): https://otsuka-us.com/media/static/Simtriyo-PI.pdf - [3] Otsuka America Pharmaceutical — centanafadine FDA review and approval updates: https://www.otsuka-us.com/otsuka-shares-fda-review-update-for-centanafadine - [4] Psychiatry Advisor — 'Simtriyo Gains FDA Approval as First NDSRI CNS Stimulant for ADHD' (2026): https://www.psychiatryadvisor.com/news/fda-approves-simtriyo-centanafadine-adhd/ - [5] American Academy of Pediatrics — 'Clinical Practice Guideline for the Diagnosis, Evaluation, and Treatment of Attention-Deficit/Hyperactivity Disorder in Children and Adolescents', Pediatrics (2019): https://publications.aap.org/pediatrics/article/144/4/e20192528/81590/ - [6] U.S. Centers for Disease Control and Prevention — 'Data and Statistics About ADHD': https://www.cdc.gov/adhd/data/index.html - [7] U.S. National Institute of Mental Health — 'Attention-Deficit/Hyperactivity Disorder (ADHD)' statistics: https://www.nimh.nih.gov/health/statistics/attention-deficit-hyperactivity-disorder-adhd - [8] ClinicalTrials.gov — Study 1, centanafadine in children aged 6–12 (NCT05428033): https://clinicaltrials.gov/study/NCT05428033 - [9] ClinicalTrials.gov — Study 2, centanafadine in adolescents aged 13–17 (NCT05257265): https://clinicaltrials.gov/study/NCT05257265 - [10] ClinicalTrials.gov — Study 3, centanafadine in adults (NCT03605680): https://clinicaltrials.gov/study/NCT03605680 - [11] ClinicalTrials.gov — Study 4, centanafadine in adults (NCT03605836): https://clinicaltrials.gov/study/NCT03605836 - [12] U.S. Food and Drug Administration — 'Drugs@FDA: FDA-Approved Drugs' (search 'centanafadine'): https://www.accessdata.fda.gov/scripts/cder/daf/ --- _Canonical article: [https://brainwavepost.com/article/simtriyo-centanafadine-adhd-complete-guide-2026](https://brainwavepost.com/article/simtriyo-centanafadine-adhd-complete-guide-2026) — © BrainWavePost. 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