Amphetamine/dextroamphetamine is a prescription stimulant medication used primarily to treat attention deficit hyperactivity disorder (ADHD) and narcolepsy. You may recognize it by its most common brand name, Adderall. The generic name refers to a combination of four amphetamine salts that work together to improve focus, attention, and impulse control. It is one of the most widely prescribed ADHD medications in the United States.
What the Medication Actually Contains
The name “amphetamine/dextroamphetamine” describes two closely related compounds. Dextroamphetamine (the “dextro” or right-handed form) and levoamphetamine (the “levo” or left-handed form) are mirror images of each other at the molecular level, and they affect the brain slightly differently. Dextroamphetamine has a stronger effect on focus and attention, while levoamphetamine contributes more to physical alertness and energy. The medication contains a roughly 3:1 ratio of dextroamphetamine to levoamphetamine, a blend designed to balance mental and physical symptom relief.
Both compounds work by increasing levels of dopamine and norepinephrine in the brain. These are chemical messengers involved in attention, motivation, and executive function. In people with ADHD, where these signaling pathways are underactive, the medication helps restore more typical brain activity.
FDA-Approved Uses
The FDA has approved amphetamine/dextroamphetamine for two conditions: ADHD and narcolepsy. For ADHD, it is approved for use in children aged 3 and older (immediate-release) or 6 and older (extended-release), as well as adolescents and adults. For narcolepsy, a sleep disorder that causes overwhelming daytime drowsiness and sudden sleep episodes, it helps people stay awake during the day.
Immediate-Release vs. Extended-Release
The medication comes in two main formulations. The immediate-release (IR) tablet provides symptom relief for about 4 to 6 hours per dose, which means most people take it two or three times a day. The first dose is typically taken in the morning, with additional doses spaced throughout the day. The extended-release (XR) capsule is taken once daily in the morning and is designed to release medication gradually over a longer period, eliminating the need for midday doses.
The choice between IR and XR often comes down to lifestyle and symptom patterns. Some people prefer the flexibility of IR tablets, which allow them to adjust timing and skip afternoon doses on days when they don’t need coverage. Others prefer the convenience and steadier effect of taking a single XR capsule each morning. Both formulations contain the same active ingredients.
Common Side Effects
Side effects are common, particularly when starting the medication or adjusting the dose. In clinical trials of the extended-release version, the most frequently reported issues varied by age group but followed a clear pattern.
Loss of appetite is the most consistent side effect across all ages. In trials, 22% of children aged 6 to 12, 36% of adolescents, and 33% of adults experienced reduced appetite, compared to just 2% to 4% of those taking a placebo. This appetite suppression can lead to weight loss, which is why growth monitoring is standard practice for children and teens on the medication.
Insomnia is the second major concern. It affected 17% of children, 12% of adolescents, and 27% of adults in trials. Because the medication is a stimulant, taking it too late in the day can make it difficult to fall asleep. Dry mouth is particularly common in adults, reported by 35% of adult trial participants compared to 5% on placebo. Other side effects can include headache, nervousness, stomach pain, and increased heart rate.
Serious Risks and Warnings
Amphetamine/dextroamphetamine carries the FDA’s most serious warning, a boxed warning, for two reasons. First, it has a high potential for abuse and dependence. Prolonged use can lead to psychological or physical dependence, and the medication is sometimes misused for its stimulant effects by people without ADHD. Second, misuse can cause sudden death and serious cardiovascular events.
The medication is classified as a Schedule II controlled substance by the DEA, the same category as oxycodone and fentanyl. This classification means prescriptions cannot be called into a pharmacy over the phone in most states, refills are not automatically permitted, and you typically need a new written or electronic prescription each time.
Who Should Not Take It
Certain medical conditions make this medication unsafe. It is contraindicated for people with symptomatic cardiovascular disease, moderate to severe high blood pressure, overactive thyroid, or glaucoma. People with a history of drug abuse are also not candidates for the medication due to its high addiction potential.
One critical drug interaction to know: amphetamine/dextroamphetamine must not be taken within 14 days of using a type of antidepressant called an MAOI (monoamine oxidase inhibitor). Combining the two can trigger a dangerous spike in blood pressure known as a hypertensive crisis. Anyone with a known allergy to amphetamine-class stimulants should also avoid it.
How Long It Stays in Your System
The two amphetamine components leave the body at slightly different rates. The dextroamphetamine portion has an average half-life of about 10 to 11 hours, while the levoamphetamine portion lingers a bit longer at 11.5 to nearly 14 hours. A “half-life” is the time it takes for half the drug to be cleared from your bloodstream. In practical terms, this means the medication is largely out of your system within two to three days after your last dose, though traces can be detected longer on drug screenings.
Factors like urine pH, age, and kidney function can speed up or slow down elimination. Acidic urine clears the drug faster, while more alkaline urine slows it down.
Brand Names and Generic Availability
Adderall (immediate-release) and Adderall XR (extended-release) are the best-known brand names. Multiple generic versions are now available from various manufacturers, which is why many pharmacy labels simply read “amphetamine/dextroamphetamine” or “mixed amphetamine salts.” The generic versions contain the same active ingredients and are considered therapeutically equivalent by the FDA, though some patients report subjective differences between manufacturers in how the medication feels or how long it lasts.