# Mydayis ### (dextroamphetamine sulfate, dextroamphetamine saccharate, amphetamine aspartate monohydrate, amphetamine sulfate) **[Mydayis](https://wiki.joshnp.com/books/drug-library/page/mydayis)** (mixed salts of a single-entity amphetamine product); CII
[**Full Prescribing Information**](https://dailymed.nlm.nih.gov/dailymed/fda/fdaDrugXsl.cfm?setid=141a7970-3f06-44ea-9ab7-aeece2c085fc&type=display)[**DailyMed Drug Information**](https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=141a7970-3f06-44ea-9ab7-aeece2c085fc)
--- ### **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](https://wiki.joshnp.com/link/9) 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](https://wiki.joshnp.com/link/9) instead. - **Narcolepsy** (ICD-10: G47.419): off-label at every age; insufficient. Use an approved product: [Adderall](https://wiki.joshnp.com/link/8), [Zenzedi](https://wiki.joshnp.com/link/34), [Dexedrine Spansule](https://wiki.joshnp.com/link/118). - **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** 1. 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 2. LactMed. Amphetamine. Drugs and Lactation Database, National Institute of Child Health and Human Development. 2025. https://www.ncbi.nlm.nih.gov/books/NBK501307/ 3. openFDA. NDC Directory, generic\_name "amphetamine aspartate". US Food and Drug Administration. 2026. https://api.fda.gov/drug/ndc.json 4. 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/