LisdexamfetamineLisdexamfetamine Dimesylate

About Lisdexamfetamine

Lisdexamfetamine is a prodrug that the body converts to dextroamphetamine; how it helps ADHD and binge eating disorder is not known. It is labeled for ADHD in adults and children 6 and older and for moderate to severe binge eating disorder in adults, but not for weight loss, and it is not recommended under age 6, as children that young had higher drug levels and more side effects, such as weight loss. For ADHD it starts at 30 mg each morning and is adjusted by 10 or 20 mg about weekly, up to 70 mg a day; for binge eating disorder it starts at 30 mg and rises by 20 mg about weekly to 50 to 70 mg, and it is stopped if binge eating does not improve. Severe kidney impairment limits the dose to 50 mg a day, and end-stage kidney disease to 30 mg.

The boxed warning says it has a high potential for abuse and misuse, which can lead to a substance use disorder, including addiction, and to overdose and death, a risk raised by higher doses or unapproved routes; prescribers assess each patient’s risk before and during treatment and teach safe storage and disposal. It must not be taken by anyone allergic to amphetamine products or with, or within 14 days of, an MAO inhibitor. Other warnings cover sudden death in serious heart disease, raised blood pressure and heart rate, psychotic or manic symptoms, slowed growth in children, poor circulation in the fingers and toes, serotonin syndrome and new or worse tics. In ADHD, decreased appetite, weight loss, trouble sleeping, dry mouth, irritability, anxiety, upper stomach pain, nausea, vomiting, diarrhea and dizziness are common; in binge eating disorder, dry mouth, trouble sleeping, decreased appetite, a faster heart rate, constipation, feeling jittery and anxiety.

As a Schedule II drug it cannot be refilled; each fill needs a new prescription. The Vyvanse label lets a prescriber switch between capsules and chewable tablets milligram for milligram, but no form is rated equivalent to another, so the pharmacy fills the form written. The first generics of both Vyvanse forms were approved on August 25, 2023; Arynta, a 10 mg per mL oral solution approved in June 2025, has none. The label notes a higher risk of premature delivery and low birth weight in babies of mothers dependent on amphetamines, and breastfeeding is not recommended. In October 2026 the FDA shortage list showed the capsules and chewable tablets as currently in shortage, both posted in July 2023.

Taking Lisdexamfetamine

How to take it

Once each morning, with or without food; afternoon doses can disturb sleep. Swallow capsules whole, or open one, mix the entire contents with yogurt, water or orange juice and take it right away; chew chewable tablets thoroughly; measure Arynta with the syringe and adapter supplied. Do not divide a dose or take less than one capsule or tablet a day.

If you miss a dose

Take it as soon as you remember, unless the next dose is almost due; then skip it. Do not take it in the late afternoon or evening, which can disturb sleep, and never take a double dose.

Storage

At room temperature in the original, tightly closed container, away from excess heat and moisture, in a safe place where others cannot take it; throw away Arynta 30 days after first opening. Do not flush it; use a take-back program.

Interactions to know about

Never with or within 14 days of an MAO inhibitor. Antidepressants, triptans and other serotonin-affecting medicines add a risk of serotonin syndrome, and medicines that block the enzyme CYP2D6 can raise its levels. Urine-acidifying agents such as ascorbic acid (vitamin C) lower amphetamine levels, and alkalinizing agents such as sodium bicarbonate raise them.

This summarizes the official prescribing information. Your prescriber’s and pharmacist’s instructions, and the leaflet that comes with your medicine, take priority.

Why the cash price for Lisdexamfetamine differs from pharmacy to pharmacy

Generics are rated only against the matching Vyvanse form, so a pharmacist can substitute a generic of the form written but cannot switch between forms; Arynta has no generic, and a prescription that names Vyvanse and blocks substitution is filled with the brand. Each pharmacy sets its own cash price, including its dispensing fee.

If a pharmacy can supply only part of the quantity, the rest can follow within 72 hours; after that a new prescription is needed.

Ways to pay less for Lisdexamfetamine without insurance

• Ask for generic substitution, and make sure the prescription does not name Vyvanse only.
• Confirm the pharmacy has your form and strength before the prescription is sent; an unfilled electronic prescription can be transferred only once, at your request.
• Ask for a partial fill if you want fewer at first; where state law allows, the rest can follow within 30 days of the date written.
• If chewable tablets or Arynta are prescribed, ask the prescriber whether capsules, which can be opened and mixed with yogurt, water or orange juice, would suit you.
• Upload the prescription to Script Unlock so licensed pharmacies can quote their cash price. You pay the pharmacy directly.

Questions to ask your pharmacist about Lisdexamfetamine

1. 1.Can you fill my form, strength and full quantity?
2. 2.Is the generic you would give me rated equivalent to Vyvanse?
3. 3.Is it safe with my antidepressant, migraine medicine or other medicines?
4. 4.How do I open a capsule and mix it if my child cannot swallow it?

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