Zenzedi

(dextroamphetamine sulfate)

Zenzedi (dextroamphetamine sulfate); CII

Summary

Zenzedi is an immediate-release, short-acting dextroamphetamine tablet approved for narcolepsy and for ADHD in patients aged 3 to 16. It is single-isomer dextroamphetamine, carrying no levoamphetamine and less peripheral noradrenergic load than an equivalent mixed-salt dose. Its differentiator is the age floor: 3 years is the lowest approved age in this library, and the seven-step ladder starting at 2.5 mg is what makes that band dosable. Schedule II; brand and generic.

Forms & Strengths

• Tablets: 2.5 mg, 5 mg, 7.5 mg, 10 mg, 15 mg, 20 mg, 30 mg
• Scoring: the 5 mg tablet is scored, the 10 mg tablet double scored

Dosing

• Age:
  • ADHD: 3-16 y/o, the lowest approved age here. Not recommended under 3
  • Narcolepsy: no age bound stated; dose ladder given from age 6
• Onset: 30-60 min
• Duration: 4-6 hours, the label's own redosing interval
• Initial Dose:
  • ADHD, 3-5 y/o: 2.5 mg daily
  • ADHD, 6-16 y/o: 5 mg once or twice daily
  • Narcolepsy, 6-11 y/o: 5 mg daily
  • Narcolepsy, ≥ 12 y/o: 10 mg daily
• Titration:
  • ADHD, 3-5 y/o: 2.5 mg at weekly intervals until optimal response
  • ADHD, 6-16 y/o: 5 mg at weekly intervals until optimal response
  • Narcolepsy, 6-11 y/o: 5 mg at weekly intervals
  • Narcolepsy, ≥ 12 y/o: 10 mg at weekly intervals
• Max Dose:
  • ADHD, 6-16 y/o: 40 mg/day; only in rare cases will it be necessary to exceed this
  • ADHD, 3-5 y/o: no maximum stated in this label. Titrate to optimal response; 40 mg/day is not transferable downward to a preschooler
  • Narcolepsy: usual range 5-60 mg/day in divided doses
• Considerations: First dose on waking, one or two further doses at 4 to 6 hour intervals; avoid late evening doses. The label directs interrupting treatment occasionally to test continued need.

Pharmacology

• Mechanism: Blocks reuptake at DAT and NET and promotes presynaptic catecholamine release via VMAT2 and TAAR1; the release component distinguishes amphetamines from methylphenidate
• Delivery / Release: Immediate release. Cmax 36.6 ng/mL at about 3 hours, against 23.5 ng/mL at 8 hours for the SR capsule
• Formulation: Single-isomer dextroamphetamine sulfate; no levoamphetamine
• Metabolism: CYP2D6 to 4-hydroxyamphetamine. Half-life about 12 hours; the shorter duration is the peak-and-fall profile, not faster clearance
• Pharmacogenomics: No genotype-directed dosing in the label; the actionable consequence is the CYP2D6-inhibitor interaction
• Class Positioning: A higher earlier peak than Dexedrine Spansule, a finer ladder, and the 3 to 5 year band it lacks. Single-isomer where IR Adderall is mixed salts

Indications

• Narcolepsy (ICD-10: G47.419): no age bound stated; dosing from age 6
• ADHD (ICD-10: F90.0, F90.1, F90.2, F90.8, F90.9): patients 3 to 16 y/o, within a total treatment program

Off-Label Uses

• Preschool ADHD, where approval and guideline diverge (ICD-10: F90.x): FDA approves from age 3; evidence for amphetamine in preschoolers is limited.
• AAP places behavioral parent training first-line at 4 to under 6 (grade A) and names methylphenidate, not amphetamine, if medication is added (AAP 2019).
• ADHD at 17 and older (ICD-10: F90.x): this label stops at 16; switch to a product with an adult indication.
• Binge eating disorder (ICD-10: F50.81): lisdexamfetamine holds it, adults only; insufficient here.
• Where the evidence does not support use: depression augmentation; no pediatric evidence for IR dextroamphetamine (AHRQ 2024).
• Cognitive enhancement without ADHD: not an indication.

Contraindications & Warnings

• Boxed Warning: Abuse, misuse, and addiction; misuse can cause overdose and death. Assess abuse risk and monitor throughout.
• Contraindicated:
  • Known hypersensitivity to amphetamine products
  • MAOI use, current or within 14 days
• Use with caution (label Warnings, not contraindications):
  • Structural cardiac abnormality or serious arrhythmia; the label says avoid
  • Pre-existing hypertension; blood pressure and heart rate rise
  • Psychosis or bipolar disorder
  • Prior seizure or EEG abnormality
  • Peripheral vasculopathy including Raynaud phenomenon
  • Tics or Tourette syndrome, personal or family
  • Substance use disorder, patient or household
  • The 3 to 5 year band: no maximum stated, long-term pediatric effects not established. Hold at the lowest effective dose
• Screen before starting:
  • Cardiac and family history of sudden death; ECG only if positive
  • Tics and Tourette syndrome, in child and family
  • Mania risk factors, including family history
  • Household abuse and diversion risk
  • Baseline height, weight, blood pressure and heart rate
  • Whether behavioral treatment has been tried, for any child under 6 (AAP 2019)

Drug Interactions

• MAOIs (phenelzine, tranylcypromine, selegiline, linezolid): hypertensive crisis and malignant hyperpyrexia, sometimes fatal. Do not give within 14 days.
• Serotonergic agents (SSRIs, SNRIs, TCAs, triptans, fentanyl, lithium, tramadol): serotonin syndrome; counsel on symptoms and stop both if it occurs.
• CYP2D6 inhibitors (paroxetine, fluoxetine, quinidine, ritonavir): raise exposure; start lower.
• Alkalinizing agents (sodium bicarbonate, acetazolamide): raise absorption and reduce excretion; avoid or reduce the dose.
• Acidifying agents (ascorbic acid, fruit juices, methenamine): lower absorption and raise excretion; adjust on response.
• Tricyclics (desipramine, protriptyline): sustained rise in brain d-amphetamine; monitor.
• Antiepileptics (phenytoin, phenobarbital, ethosuximide): delayed absorption; separate dosing, check levels after a stimulant change.
• Antihypertensives and antihistamines: effects antagonised; recheck blood pressure, and do not rely on an antihistamine for sleep.
• Chlorpromazine and haloperidol: inhibit the stimulant effect; expect loss of benefit.

Administration

• First dose on waking, further doses at 4 to 6 hour intervals.
• Avoid late evening doses; a third dose in a young child costs sleep.
• Splitting a scored tablet is legitimate for an intermediate dose where 2.5 mg is not stocked.
• Prescribe at the lowest effective dosage.
• Interrupt treatment occasionally to see whether therapy is still needed; this label makes that explicit.
• If a dose is missed, skip it; do not double up.
• Store securely, preferably locked, in a child-resistant container.

Side Effects

• Common: loss of appetite, weight loss, insomnia, overstimulation, restlessness, dry mouth, headache, dizziness, tremor, dysphoria, palpitations, raised blood pressure
• Serious:
  • Sudden death with structural cardiac disease. Investigate exertional chest pain or syncope.
  • Psychotic episodes at recommended doses (rare), mania and new aggression. Consider discontinuing.
  • Serotonin syndrome. Stop both drugs and treat supportively.
  • Seizures. Discontinue.
  • Peripheral vasculopathy with digital ulceration. Reduce or stop.
  • Growth suppression. Interrupt if height or weight gain falls behind.
  • New or worsening motor and verbal tics. Discontinue if clinically appropriate.
  • Prolonged erections; painful erection beyond a few hours is a surgical emergency.

Monitoring & Labs

• Cardiovascular: heart rate and blood pressure at baseline, each dose change, and every 6 months.
• Growth, 6 to 16 y/o: height, weight and BMI charted at baseline and every 6 months; interrupt if two percentile lines are crossed.
• Growth, 3 to 5 y/o: height, weight and BMI at baseline and every 3 months; with no dose ceiling here, growth is the ceiling.
• Appetite and Sleep: at every visit and dose change; ask when the last dose is given.
• Psychiatric and tics: psychosis, mania, aggression and new tics at every visit.
• Peripheral vasculopathy: inspect fingers and toes at every visit.
• Continued need: schedule a deliberate interruption at least annually, per this label.
• Abuse and Diversion: adherence, pill counts and PDMP check at every refill.
• Age boundary: review the indication at the 17th birthday. No routine labs.

Discontinuation & Taper

• May be stopped abruptly at therapeutic doses; no taper is required.
• Withdrawal after abrupt stop following prolonged use: dysphoria, fatigue, vivid dreams, increased appetite.
• Rebound at 4 to 6 hours is offset, not withdrawal; the family may be describing the gap between doses.
• Planned interruption is a labelled instruction here: stop occasionally to test whether symptoms recur at a level requiring continued therapy.
• Interrupt treatment where growth or weight gain falls behind.

Pregnancy & Lactation

• Pregnancy: No adequate controlled studies; animal teratogenicity only far above human doses. Amphetamine-dependent mothers have more premature delivery and low birth weight. Use only if benefit justifies fetal risk.
• Lactation: Label advises against nursing. LactMed: infant dose about 5.7% of the maternal weight-adjusted dose, all four infants studied growing normally. (LactMed 2025)
• Milk supply: Dose-related prolactin suppression up to 40% may impair production before lactation is established. (LactMed 2025)
• Exposure Registry: None on this label; the National Pregnancy Registry for Psychostimulants (1-866-961-2388) takes amphetamine exposures.

Counseling Points

• Counsel the family on:

  • The 4 to 6 hour window and the need for a second, sometimes third, dose.
  • For a preschooler: AAP puts behavioral parent training first and names a different class at that age.
  • For a preschooler: no maximum dose is set, so the growth chart is the ceiling, checked every three months.
  • The 2.5 mg tablet has only one generic supplier; if the pharmacy cannot fill it, split a scored 5 mg tablet.
  • The planned yearly interruption, so it is not heard later as doubt about the diagnosis.
  • Vitamin C and fruit juice can mimic treatment failure; bicarbonate and antacids raise levels.
  • Moving the largest meal to breakfast and to the evening.
  • Locked storage and the child-resistant container.

• Advise them to call for:

  • Chest pain on exertion, fainting, or a racing heart that does not settle.
  • New hallucinations, or a young child describing things that are not there.
  • Numbness, coldness or colour change in the fingers or toes.
  • A new or markedly worse tic, or a seizure of any kind.
  • Weight loss, or shoes still fitting after several months.
  • A painful erection lasting more than a few hours.
  • Agitation, shivering, sweating or confusion after an antidepressant change.

References

1. DailyMed. ZENZEDI (dextroamphetamine sulfate) tablets, USP prescribing information. Azurity Pharmaceuticals. https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=d6394df5-f2c9-47eb-b57e-f3e9cfd94f84
2. LactMed. Dextroamphetamine. Drugs and Lactation Database, National Institute of Child Health and Human Development. 2025. https://www.ncbi.nlm.nih.gov/books/NBK501740/
3. openFDA. NDC Directory, generic_name "dextroamphetamine". US Food and Drug Administration. 2026. https://api.fda.gov/drug/ndc.json
4. American Academy of Pediatrics. Clinical Practice Guideline for the Diagnosis, Evaluation, and Treatment of Attention-Deficit/Hyperactivity Disorder in Children and Adolescents. Pediatrics 144(4):e20192528. 2019. https://publications.aap.org/pediatrics/article/144/4/e20192528/81590/Clinical-Practice-Guideline-for-the-Diagnosis
5. Agency for Healthcare Research and Quality. ADHD Diagnosis and Treatment in Children and Adolescents. Comparative Effectiveness Review No. 267. 2024. https://www.ncbi.nlm.nih.gov/books/NBK602989/