Adderall is composed of four amphetamine salts combined in equal parts by weight: dextroamphetamine sulfate, amphetamine sulfate, dextroamphetamine saccharate, and amphetamine aspartate monohydrate. This specific blend produces a 3-to-1 ratio of dextroamphetamine to levoamphetamine, the two mirror-image forms of the amphetamine molecule. That ratio is central to how the drug works and what sets it apart from other stimulant medications.
The Four Active Salts
Each Adderall tablet or capsule contains equal weights of its four salts. Two of those salts (dextroamphetamine sulfate and dextroamphetamine saccharate) deliver only the “dextro” form of amphetamine. The other two (amphetamine sulfate and amphetamine aspartate monohydrate) contain a 50/50 mix of both the dextro and levo forms. When you add it all up, roughly 75% of the active amphetamine in the pill is dextroamphetamine and 25% is levoamphetamine.
The distinction matters because these two forms hit the brain differently. Dextroamphetamine is three to five times more potent than levoamphetamine at stimulating the release of dopamine, norepinephrine, and serotonin. It also blocks the reuptake of those chemicals, keeping them active in the brain longer. This is the component most responsible for improved focus and wakefulness. Levoamphetamine has a milder central nervous system effect but contributes more to peripheral effects like increased heart rate and blood pressure. The combination is designed to produce a balanced clinical profile: strong enough focus-enhancing effects from the dextro side, with a smoother onset and longer-lasting action from the levo side.
Immediate-Release vs. Extended-Release
Adderall comes in two formulations, and their compositions differ in important ways beyond just the active ingredients.
The immediate-release (IR) tablet dissolves in the stomach and releases all four salts at once. It comes in strengths from 5 mg to 30 mg. The extended-release (XR) capsule contains two types of tiny beads: one set that dissolves immediately and a second set coated in a pH-sensitive polymer (methacrylic acid copolymer) that delays release until the beads reach a more alkaline part of the intestine. This effectively delivers two doses from a single capsule, with the second wave hitting several hours after the first. XR capsules are available in 5 mg through 30 mg strengths.
Inactive Ingredients
The non-active components differ between formulations and even between tablet strengths. In immediate-release tablets, inactive ingredients include microcrystalline cellulose (a binder that holds the tablet together), corn starch, magnesium stearate (a lubricant used in manufacturing), compressible sugar made from sucrose and maltodextrin, colloidal silicon dioxide, and saccharin sodium.
Color additives vary by dose. The 5 mg tablet is white and contains no dyes. The 7.5 mg and 10 mg tablets contain FD&C Blue #1. The 12.5 mg, 15 mg, 20 mg, and 30 mg tablets contain FD&C Yellow #6. If you have a sensitivity to artificial dyes, this is worth noting when discussing dose options.
The XR capsules contain a different set of inactive ingredients to support the bead-release system: gelatin for the capsule shell, hydroxypropyl methylcellulose, sugar spheres (the core of each bead), talc, and triethyl citrate.
How Stomach Acidity Affects Absorption
Amphetamine salts are chemically sensitive to the pH of your digestive system, and this can meaningfully change how much of the drug your body absorbs. Acidic conditions in the stomach and gut reduce absorption. Foods and drinks that lower pH, like citrus juice and vitamin C (ascorbic acid), can blunt the drug’s effects. Alkaline substances like antacids do the opposite, increasing absorption. The FDA prescribing information specifically warns against taking Adderall XR with antacids for this reason.
This pH sensitivity also affects how quickly the drug leaves your body. Acidic urine speeds up elimination, while alkaline urine slows it down. So two people taking the same dose can experience noticeably different effects depending on their diet and what other medications or supplements they take.
How Adderall Differs From Other Stimulants
The mixed-salt composition is what distinguishes Adderall from other prescription stimulants. Medications like Dexedrine contain only dextroamphetamine, delivering a more potent but shorter-acting effect. Vyvanse uses a prodrug form of dextroamphetamine that the body must convert before it becomes active, producing a smoother curve. Ritalin and Concerta use an entirely different molecule, methylphenidate, which works through a related but distinct mechanism.
Adderall’s specific 3-to-1 ratio was designed to combine the stronger cognitive effects of dextroamphetamine with the longer peripheral action of levoamphetamine. The use of four different salt forms (sulfate, saccharate, aspartate, and the mixed sulfate) also contributes to a staggered absorption pattern, even in the immediate-release tablet, because different salts dissolve at slightly different rates.