Amphetamine salts ER is a prescription stimulant medication used to treat ADHD. The “ER” stands for extended release, meaning the capsule is designed to deliver medication steadily over 8 to 12 hours instead of all at once. You may recognize it by the brand name Adderall XR, though it’s widely available as a generic. It contains a mix of amphetamine and dextroamphetamine, two closely related stimulants that work together to improve focus and impulse control.
What “Amphetamine Salts ER” Means on Your Label
If you see “amphetamine salts ER” on a pharmacy label, you’re looking at the generic version of Adderall XR. The word “salts” refers to the specific chemical forms of amphetamine in the pill. Four different salt forms are combined in equal parts: dextroamphetamine saccharate, amphetamine aspartate, dextroamphetamine sulfate, and amphetamine sulfate. This isn’t something you need to memorize. What matters is that “ER” (extended release) distinguishes it from the immediate-release version, sometimes labeled “amphetamine salts” without the ER.
Mydayis is another brand-name extended-release formulation of the same active ingredients, approved for adults and adolescents 13 and older.
How the Extended-Release Capsule Works
Each capsule contains two types of tiny beads. About half of the beads dissolve quickly after you swallow the capsule, releasing the first dose of medication within the first hour or so. The remaining beads have a special coating that resists stomach acid, so they don’t dissolve until roughly four hours later when they reach the intestines. This creates a “double pulse” of medication that mimics taking two separate doses without actually having to take a second pill.
The result is a smoother, longer arc of symptom relief. Blood levels of the medication peak around 7 hours after you take it, compared to about 3 hours for the immediate-release tablet. The extended-release version provides coverage for roughly 8 to 12 hours on a single morning dose.
How It Differs From Immediate Release
The immediate-release tablet (Adderall IR) is an uncoated pill that dissolves all at once in the stomach. It kicks in faster but wears off in about 4 to 6 hours, so most people need to take it twice a day. That rapid rise and fall can mean a noticeable “crash” as the medication leaves your system, with focus dropping off sharply in the afternoon.
With the extended-release capsule, the sustained delivery tends to produce a more gradual onset and a gentler decline. Some people prefer the immediate-release version because it offers more flexibility. For instance, you can skip the afternoon dose on days when you don’t need full-day coverage, or adjust timing around your schedule. The extended-release version trades that flexibility for convenience and a steadier experience throughout the day.
What It’s Prescribed For
Amphetamine salts ER is FDA-approved for ADHD in adults and children ages 6 and older. The immediate-release form is also approved for narcolepsy, a condition involving uncontrollable daytime sleepiness, though that use is less common.
The medication works by increasing the activity of two chemical messengers in the brain: dopamine and norepinephrine. Amphetamine enters nerve cells through the same transport channels these messengers use. Once inside, it causes stored dopamine and norepinephrine to flood out of their storage compartments and into the spaces between nerve cells, boosting signaling in brain circuits that control attention, motivation, and impulse regulation. In people with ADHD, these circuits are typically underactive, which is why a stimulant can paradoxically help with focus and calm.
Typical Doses
For children ages 6 to 12, the usual starting dose is 10 mg once daily in the morning, with adjustments in 5 or 10 mg steps each week. The maximum recommended dose for this age group is 30 mg per day. Adolescents ages 13 to 17 also typically start at 10 mg, with the option to increase to 20 mg after one week. Adults starting treatment for the first time generally begin at 20 mg per day.
Because the capsule is designed for once-daily dosing, it’s almost always taken in the morning. Taking it later in the day can interfere with sleep.
Common Side Effects
The most frequently reported side effects are decreased appetite, trouble sleeping, dry mouth, and increased heart rate. Some people notice irritability, anxiety, or a jittery feeling, especially when starting the medication or after a dose increase. Weight loss is common because appetite suppression can be significant, particularly in the first few months. Children on long-term treatment are sometimes monitored for growth, since reduced food intake can slow weight gain.
Because the extended-release version keeps medication levels elevated for longer, side effects like insomnia and appetite loss can last further into the evening compared to the immediate-release tablet. On the other hand, the immediate-release form tends to produce sharper peaks and more abrupt side effects that come and go quickly.
Important Safety Information
Amphetamine salts ER is classified as a Schedule II controlled substance by the DEA, the same category as oxycodone and fentanyl. This reflects its high potential for misuse and dependence. The FDA’s most prominent warning on the label (a boxed warning) specifically addresses the risk of abuse, misuse, and addiction. Misuse at higher doses or through non-oral routes like crushing and snorting significantly raises the risk of overdose and death.
In practice, this scheduling means your prescription cannot include automatic refills. You’ll need a new prescription each time, and many states limit each prescription to a 30-day supply.
There are also cardiovascular precautions. Sudden death has been reported in rare cases among patients with pre-existing structural heart defects, serious arrhythmias, or coronary artery disease. For most healthy people, stimulants cause modest increases in heart rate and blood pressure that aren’t dangerous, but a cardiac history should be disclosed before starting treatment.
Amphetamine salts ER should not be taken alongside a class of older antidepressants called MAOIs, as the combination can theoretically cause dangerous spikes in blood pressure. A washout period of at least 14 days is standard before switching between the two.