Amphetamine: uses, dosing, side effects & brands

Amphetamine Sulfate is a central nervous system stimulant used to treat Attention Deficit Disorder with Hyperactivity, Narcolepsy.

The FDA classifies amphetamine as a central nervous system stimulant. CNS stimulants raise the levels of the brain's signaling chemicals dopamine and norepinephrine, either by releasing more of them or by blocking their reuptake. This heightened activity in attention and arousal circuits increases alertness, energy, and focus. If you are checking whether it is safe to combine with something else, the class is what matters — two drugs from the same class usually should not be stacked.

The elimination half-life of amphetamine is about 10 to 11 hours for d-amphetamine (range 9.8 to 11 hours) and about 12 to 14 hours for l-amphetamine (range 11.5 to 13.8 hours) in healthy adults — that is how long the body takes to clear half of a dose. These are elimination half-lives for the two amphetamine isomers themselves; l-amphetamine clears more slowly than d-amphetamine. Elimination speeds up in acidic urine and slows in alkaline urine, and can be prolonged by kidney or liver problems. Half-life is not the same as how long a drug test can detect the drug, and it varies with age, kidney and liver function.

It depends on the medicine. We check it against the FDA labels rather than guessing: our interaction checker searches each drug's own label for the other and quotes what it says, naming the section it came from. Run amphetamine against whatever else you take — and remember that a label not naming a drug is not the same as that combination being safe.

We track 4 amphetamine-containing products in the U.S.: Amphetamine Sulfate, Evekeo ODT, Adzenys ER and Adzenys XR-ODT. They are the same active ingredient; they differ in form, manufacturer, price and FDA recall record.

Across the brands we track, amphetamine is currently marketed as tablet, tablet, orally disintegrating and suspension, extended release, per the FDA's National Drug Code Directory. Each form is dosed differently — follow the label for the exact product you were prescribed.

Yes. Our catalog lists 1 generic amphetamine product alongside the brand versions. A generic has the same active ingredient and must meet the FDA's bioequivalence standard; it usually costs less. Ask your pharmacist which one your plan covers.

Other medicines: we hold source-cited interaction answers for Can you drink alcohol while taking Adderall?. This is what the FDA label and our cited sources say — it is not a complete list. Your pharmacist can check your own combination.

Adderall (a mix of amphetamine and dextroamphetamine) is a stimulant, and its everyday side effects follow from that. MedlinePlus lists nervousness, headache, dry mouth, constipation, diarrhea or nausea, changes in sex drive, and weight loss. Two of the most common — decreased appetite and trouble sleeping — track with each dose and often ease as your body adjusts or when a prescriber lowers the dose or moves it earlier in the day. Raised heart rate and blood pressure are also expected stimulant effects. This is not a complete list; report anything persistent or bothersome to your prescriber.

Get emergency help for heart symptoms: MedlinePlus says to call your doctor right away for "chest pain, shortness of breath, or fainting." The FDA label warns that stimulants like Adderall may cause sudden death, heart attack, or stroke in adults, and sudden death in children — especially those with heart defects or serious heart problems — which is why it is not used in people with serious pre-existing heart disease. Also seek immediate care for new psychiatric symptoms — "hallucinating (seeing things or hearing voices that do not exist)" or "mania (frenzied or abnormally excited mood)" — for seizures, and for "slow or difficult speech," "weakness or numbness of an arm or leg," or serotonin-syndrome signs like agitation, fever, confusion and a fast heartbeat. This is the call-now list, not the full one.

Yes. Amphetamine stimulants like Adderall carry the FDA's boxed warning — its most serious warning — for abuse and dependence. MedlinePlus states plainly that "the combination of dextroamphetamine and amphetamine can be habit-forming" and warns: "Do not take a larger dose, take it more often, or take it for a longer time than prescribed by your doctor." Adderall is a Schedule II controlled substance because of this misuse potential. Taking more than prescribed, or using someone else's prescription, raises the risk of dependence and of the cardiovascular and psychiatric harms above.

Yes — this is a specific, less-obvious risk worth watching for. MedlinePlus tells patients to call their doctor for "paleness or blue color of fingers or toes," "pain, numbness, burning, or tingling in the hands or feet," and "unexplained wounds appearing on fingers or toes." These are signs of peripheral circulation problems (including Raynaud's-type changes) linked to stimulants. Don't wait these out — report them to your prescriber promptly.

Because Adderall is a stimulant, effects like appetite loss, jitteriness and sleep trouble typically appear the same day you take it and rise and fall with each dose; immediate-release wears off in hours, so evening insomnia often means the dose is too late in the day — a timing your prescriber can adjust. Do not stop on your own: MedlinePlus warns, "Do not stop taking dextroamphetamine and amphetamine without talking to your doctor, especially if you have overused the medication," because abruptly stopping after heavy use can cause a withdrawal crash with extreme tiredness and depression. Dose changes and stopping are prescriber-managed.

"In your system" can mean two different things. The first is how long the drug is active and being cleared, which is tied to its elimination half-life. Per the FDA prescribing information, Adderall's isomers have a mean half-life of about 10 hours (d-amphetamine) and 13 hours (l-amphetamine) in adults. Because a drug is largely eliminated after roughly 4 to 5 half-lives, most of a single dose is cleared in about 2 to 3 days. The second meaning is how long a drug test can still detect amphetamine or its metabolites, which is longer than clearance and varies by test type (urine, blood, saliva, or hair). These are approximate ranges from laboratory and pharmacology references, not guarantees, and only a clinician or testing lab can interpret a specific result.

Urine is the most common screen. Mayo Clinic Laboratories indicates a typical urine detection interval for amphetamine-type stimulants of about 2 to 3 days after last use (amphetamine specifically is listed at about 3 days), and ARUP Laboratories lists a broader window of roughly 1 to 7 days; because sources vary, a single therapeutic dose is often on the shorter end (about 1 to 3 days). The exact window depends on the dose, how long and how often it was taken, individual metabolism, hydration, and the specific assay and its cutoff. Urinary pH also matters for amphetamine: more acidic urine speeds elimination and shortens the window, while alkaline urine lengthens it. These are approximate ranges, not guarantees, and only a testing lab can interpret an actual result.

Detection windows differ by specimen. In blood, amphetamine is typically detectable for a shorter period, on the order of about 24 to 48 hours (occasionally up to roughly 2 to 3 days). In saliva (oral fluid), it can appear within about 20 minutes of dosing and generally remains detectable for up to around 1 to 2 days. Hair testing has by far the longest window: because the drug is deposited in growing hair, standard hair-strand tests can detect amphetamine use for up to about 90 days (roughly 3 months) after the last dose. All of these are approximate laboratory ranges that vary with dose, frequency of use, and the assay; only a clinician or testing lab can interpret a specific result.

Several factors shift the ranges above. Dose and frequency matter most: a single therapeutic dose clears faster than chronic or high-dose use, which can extend detection. Metabolism, age, and liver and kidney function affect how quickly amphetamine is eliminated, so slower metabolizers and people with reduced organ function may test positive longer. Body composition and hydration influence concentration in urine, and urinary pH specifically changes amphetamine elimination (acidic urine shortens it, alkaline urine lengthens it). Finally, the test itself matters, its type and its cutoff concentration determine what counts as a positive. All figures here are approximate ranges from laboratory references, not guarantees. This information is factual and educational only; it is not advice about passing or altering a test, and no one should stop a prescribed medication without talking to the prescribing clinician.