Mydayis

(dextroamphetamine sulfate, dextroamphetamine saccharate, amphetamine aspartate monohydrate, amphetamine sulfate)
Mydayis (mixed salts of a single-entity amphetamine product); CII
Full Prescribing Information
DailyMed Drug Information
Summary
Mydayis is a triple-bead extended-release amphetamine capsule approved for ADHD from age 13, carrying the same four salts and 3:1 dextro to levo ratio as Adderall XR. An immediate-release bead plus two delayed-release beads unlocking at pH 5.5 and pH 7.0 give the longest coverage of any oral amphetamine here. Choose it when an adolescent needs late-evening rather than school-day coverage; it is ruled out below 13, where no safe and effective dose could be established. Schedule II; brand and generic.
Forms & Strengths
Extended-release capsules: 12.5 mg, 25 mg, 37.5 mg, 50 mg
Dosing
Age: ≥ 13 y/o; not established at 12 years and younger
Onset: 2-4 hours to measurable effect
Duration: up to 16 hours
Release Profile: Triple bead; one immediate-release plus two delayed-release beads releasing at pH 5.5 and pH 7.0. Tmax 7-10 hours pediatric, about 8 hours adult
Initial Dose:
13-17 y/o: 12.5 mg once daily on awakening
18-55 y/o: 12.5 mg once daily on awakening; 25 mg may be considered
Severe renal impairment (GFR 15 to < 30), adults: 12.5 mg once daily. ESRD not recommended at any age
Titration: 12.5 mg no sooner than weekly, at any age
Max Dose:
13-17 y/o: 25 mg/day; above 25 mg not evaluated in pediatric trials. Severe renal impairment: 12.5 mg/day
18-55 y/o: 50 mg/day; no additional benefit above 50 mg. Severe renal impairment: 25 mg/day
No dosing recommendation above age 55
Considerations: Give on awakening; effect may last 16 hours. Take consistently with or without food, since a high-fat meal delays Tmax 4.5 to 5 hours. A missed dose is skipped.
Pharmacology
Mechanism: Blocks reuptake at DAT and NET and promotes presynaptic catecholamine release via VMAT2 and TAAR1; the release component is what distinguishes amphetamines from methylphenidate
Delivery / Release: Two pH triggers rather than a timed matrix stage the second and third releases down the gut
Formulation: Four salts in equal weight, 3:1 dextro to levo. Linear over 12.5 to 50 mg, steady state days 7 to 8
Metabolism: CYP2D6 to 4-hydroxyamphetamine. Half-life 10-11 h d-amphetamine, 10-13 h l-amphetamine. Renal excretion is pH dependent
Pharmacogenomics: No genotype-directed dosing in the label; the actionable consequence is the CYP2D6-inhibitor interaction
Class Positioning: Same salts as Adderall XR plus a third pH 7.0 bead, extending 12 hours to 16, at the cost of the age-13 floor. Uniquely pH-dependent, so alkalinizers and PPIs matter more
Indications
ADHD (ICD-10: F90.0, F90.1, F90.2, F90.8, F90.9): patients ≥ 13 y/o. The only approved indication.
Off-Label Uses
ADHD in children 6 to 12 (ICD-10: F90.x): studied in two trials and rejected; negative on dose-finding. Use Adderall XR instead.
Narcolepsy (ICD-10: G47.419): off-label at every age; insufficient. Use an approved product: Adderall, Zenzedi, Dexedrine Spansule.
Binge eating disorder (ICD-10: F50.81): lisdexamfetamine holds this indication, adults only; insufficient here.
Where the evidence does not support use: depression augmentation; no pediatric evidence for triple-bead mixed salts (AHRQ 2024).
Cognitive enhancement without ADHD: not an indication; not supported.
Contraindications & Warnings
Boxed Warning: Abuse, misuse, and addiction; misuse can cause overdose and death. Assess abuse risk before prescribing and monitor frequently throughout.
Contraindicated:
Known hypersensitivity to amphetamine products or any ingredient in Mydayis
MAOI use, current or within 14 days
Use with caution (label Warnings, not contraindications):
Structural cardiac abnormality, cardiomyopathy 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
Severe renal impairment; start and maximum both halve, ESRD not recommended
Settings where substitution error is likely; the label carries a dedicated overdose warning
Screen before starting:
Cardiac and family history of sudden death or ventricular arrhythmia; ECG only if positive
Tics, Tourette syndrome and mania risk factors, including family history
Abuse and diversion risk
Baseline height, weight, blood pressure and heart rate
Baseline sleep pattern, before adding a 16-hour agent
Drug Interactions
MAOIs (phenelzine, tranylcypromine, selegiline, linezolid, IV methylene blue): hypertensive crisis; do not give within 14 days.
Serotonergic agents (SSRIs, SNRIs, TCAs, triptans, fentanyl, lithium, tramadol, buspirone, St John's Wort): serotonin syndrome; counsel on symptoms and stop both if it occurs.
CYP2D6 inhibitors (fluoxetine, paroxetine, bupropion, quinidine): raise exposure; start lower and monitor at each increase.
Alkalinizing agents (sodium bicarbonate, acetazolamide): raise levels and can unlock the beads early; avoid.
Acidifying agents (ascorbic acid, fruit juices): lower levels; adjust on response, not assumed failure.
Proton pump inhibitors (omeprazole): raise gastric pH and shift Tmax earlier; adjust timing.
Alcohol: in vitro, 20% and especially 40% alcohol increased release from the capsule; counsel on dose dumping.
Administration
Once daily on awakening; up to 16 hours of effect means later dosing costs sleep.
Take consistently with food or without, never alternating.
Swallow whole, or sprinkle the entire contents on applesauce, eaten immediately without chewing. Do not store.
Do not divide a capsule; sprinkling is a swallowing accommodation, not a dose split.
If a dose is missed, skip it and resume the next morning; never make it up.
Switching from another amphetamine: stop it and titrate from 12.5 mg weekly. No milligram-for-milligram conversion exists.
Store securely, preferably locked.
Side Effects
Common, 13 to 17: decreased appetite 22%, insomnia 8%, nausea 8%, irritability 6%, decreased weight 5%, dizziness 4%, upper abdominal pain 4%
Common, adults: insomnia 31%, decreased appetite 30%, weight decreased 9%, anxiety 7%, depression 3%, bruxism 2%
Serious:
Sudden death with structural cardiac disease. Investigate exertional chest pain or syncope immediately.
Psychosis, mania and new aggression. Consider discontinuing.
Serotonin syndrome. Stop both drugs and treat supportively.
Seizures. Discontinue.
Peripheral vasculopathy with digital ulceration. Reduce or stop; refer if persistent.
Growth suppression. Interrupt if height or weight gain falls behind.
New or worsening motor and verbal tics. Discontinue if clinically appropriate.
Overdose from substitution error between amphetamine products.
Monitoring & Labs
Cardiovascular: heart rate and blood pressure at baseline, each dose change, and every 6 months; act above the age-specific 95th percentile.
Growth: height, weight and BMI charted at baseline and every 6 months; interrupt if the adolescent crosses two major percentile lines.
Sleep: at every visit and dose change, asking specifically about sleep-onset latency.
Appetite and weight: at every visit and every dose change.
Psychiatric and tics: psychosis, mania, aggression, irritability and new tics at every visit.
Peripheral vasculopathy: inspect fingers and toes at every visit.
Abuse and Diversion: adherence, pill counts and PDMP check at every refill.
Renal function: at baseline where impairment is suspected, and annually.
Laboratory: none routinely.
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 irritability and hunger land late in the evening with a 16-hour agent, not after school.
Interrupt treatment where growth or weight gain falls behind.
Drug holidays fit poorly here; where appetite or growth is limiting, switch to a shorter product instead.
Pregnancy & Lactation
Pregnancy: Data insufficient to inform a risk of major birth defects or miscarriage. Premature delivery and low birth weight reported. Monitor exposed newborns for withdrawal.
Lactation: Label says breastfeeding is not recommended. Relative infant dose 2 to 13.8%, milk/plasma ratio 1.9 to 7.5; no reported infant adverse effects.
Milk supply: Dose-related prolactin suppression up to 40% may impair production before lactation is established. (LactMed 2025)
Exposure Registry: National Pregnancy Registry for Psychiatric Medications, 1-866-961-2388.
Counseling Points
Counsel the family on:
The 16-hour duration is both the reason for choosing it and the reason to watch sleep in week one.
Dosing on waking every day and never taking a missed dose later; a noon dose is a sleepless night.
Taking it the same way daily, with or without food, because switching moves the peak by about five hours.
Alcohol releases amphetamine faster from this capsule in laboratory testing.
Antacids and reflux medicines change when the later beads open, because they unlock on gut pH.
Never swapping this for another amphetamine capsule at the same milligrams; Mydayis 37.5 mg is not Adderall XR 37.5 mg.
Sprinkling being a swallowing accommodation, not a dose split.
Locked storage; sharing or selling a Schedule II medication is a felony.
Advise them to call for:
Chest pain on exertion, fainting, or a racing heart that does not settle.
New hallucinations, or new suspicious or fearful thinking.
Numbness, coldness or colour change in the fingers or toes.
A new or markedly worse tic, or a seizure of any kind.
Falling asleep after 1 am on more than a night or two.
Weight loss, or clothes fitting more loosely over a few weeks.
Agitation, shivering, sweating or confusion after an antidepressant change.
References
DailyMed. MYDAYIS (dextroamphetamine sulfate, dextroamphetamine saccharate, amphetamine aspartate monohydrate, and amphetamine sulfate) extended-release capsules prescribing information. Takeda Pharmaceuticals America. Revised 4/2026. https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=141a7970-3f06-44ea-9ab7-aeece2c085fc
LactMed. Amphetamine. Drugs and Lactation Database, National Institute of Child Health and Human Development. 2025. https://www.ncbi.nlm.nih.gov/books/NBK501307/
openFDA. NDC Directory, generic_name "amphetamine aspartate". US Food and Drug Administration. 2026. https://api.fda.gov/drug/ndc.json
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/