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An alarm clock with two Rx tablets: How long does Adderall last?
Drug Info

How long does Adderall last?

Adderall typically lasts an average of 4-6 hours. Here’s what you should know.
Karen Berger medical writer and reviewer headshot
By | Apr. 2, 2024

Key takeaways

  • Adderall and Adderall XR are central nervous system stimulant drugs. Both medications are used to treat ADHD; Adderall can also be used to treat narcolepsy.

  • A dose of Adderall lasts for about 4 to 6 hours. A dose of Adderall XR lasts about 8 to 12 hours.

  • Consult your healthcare provider for more information and professional medical advice about your condition and the appropriate medication.

In this article:

A diagnosis of attention-deficit hyperactivity disorder (ADHD) can feel overwhelming, but the good news is that there are many treatment options. The treatment of ADHD often involves a variety of methods, such as cognitive behavioral therapy and medications. Adults may also need work modifications, while children, adolescents, and college students may require educational interventions. 

Adderall and Adderall XR are two commonly used prescription ADHD medications. 

Adderall, which contains the active ingredients amphetamine and dextroamphetamine, is a central nervous stimulant medication that is approved by the U.S. Food and Drug Administration (FDA). Adderall can be used to treat ADHD in adults and children 3 years and older. It is also FDA-approved to treat narcolepsy in adults and children 6 years and older. This formulation is known as the immediate-release version of Adderall, which may be referred to as simply Adderall or Adderall IR.

Adderall XR is an extended-release formula. This prescription stimulant drug is FDA-approved as an ADHD medication for adults and children 6 years and older. Adderall XR is only approved for the treatment of ADHD. Unlike immediate-release Adderall, Adderall XR is not approved to treat narcolepsy. 

The two types of Adderall, Adderall and Adderall XR, are classified by the United States Drug Enforcement Administration (DEA) as Schedule II drugs. This means that these prescription medications are considered potentially dangerous and have a high potential for addiction, abuse, and dependence. 

Often, people want to know how long a dose of Adderall lasts. The duration for which Adderall is effective is about 4 to 6 hours. A dose of Adderall XR lasts an average of 8 to 12 hours. Continue reading to learn more about Adderall and Adderall XR. 

RELATED: Considering an ADHD medication? Your guide to adult ADHD treatment

How does Adderall work?

Adderall and Adderall XR are known as central nervous system (CNS) stimulants. They work by increasing levels of dopamine and norepinephrine in the brain. These stimulant effects help with the symptoms of ADHD. However, because of the way they work, these medications can also cause physical effects such as increased heart rate, high blood pressure, and other heart problems, including sudden death. 

How long does Adderall last?

Since there are two forms of Adderall, we will discuss each separately. 

Adderall

After taking a dose of immediate-release Adderall, the medicine reaches its maximum effect in approximately three hours. The effects of a dose will last from about 4 to 6 hours. The dosage of Adderall will depend on various factors, such as the user’s age and symptoms. Often, medical professionals will prescribe a morning dose, with the addition of another dose(s) to be taken at 4 to 6 hours if the individual requires additional doses. 

Whether the drug prescribed is Adderall or Adderall XR, healthcare professionals aim for the lowest effective dosage to minimize the potential risks associated with amphetamine drugs.

RELATED: Learn the short- and long-term effects of Adderall on the body

Adderall XR

After taking a dose of Adderall XR, the medicine reaches its maximum effect in about seven hours. The effect of a dose will last 8 to 12 hours. As with Adderall, the dosage of Adderall XR will depend on various factors, such as the patient’s age and symptoms. However, because Adderall XR is formulated to last up to 12 hours, this medication is only taken once daily. Additional daily doses are not needed.

Factors that impact the duration of Adderall

A half-life of a drug is the time it takes for about half of the drug to be eliminated from the body. It takes about five half-lives for a drug to be almost eliminated from the body. The half-life of Adderall ranges from about 9 to 14 hours, depending on various factors, such as the age of the individual. The half-life of Adderall XR is similar to that of Adderall. 

After a dose of Adderall or Adderall XR is taken, in about 9 to 14 hours, about half of the dose is eliminated from the body. It takes about 45 to 70 hours (five half-lives) for most of the drug to be eliminated from the body. However, this calculation only applies to the last or last use of the medication if no more medicine is taken because if you continue to take more doses, the drug will go both in and out of the body. Let’s look at factors that may affect the duration of Adderall’s effects.

Food

Adderall or Adderall XR can be taken with or without food, according to the prescribing information. The effects of food have not been studied with immediate-release Adderall. With Adderall XR, food does not affect how the medication is absorbed, but a meal high in fat can take longer to reach its full effect. 

RELATED: Everything to eat (and avoid) if you have ADHD

Opening the Adderall XR capsule

Because the Adderall XR capsule is extended-release, it must be swallowed whole and not chewed or crushed. However, some individuals, especially pediatric patients, who cannot swallow pills such as the Adderall XR capsule are instructed to open the capsule and sprinkle the medication on applesauce, swallowing the mixture immediately. Doing so will not speed up the absorption of Adderall XR; it will absorb similarly to swallowing the capsule whole. 

Drugs that may affect Adderall absorption

Adderall and Adderall XR have many drug interactions with various effects to consider. For example:

  • Combining Adderall or Adderall XR with a monoamine oxidase inhibitor (MAOI) drug (or taking them within 14 days of each other) can cause dangerously high blood pressure, which can cause heart attack, stroke, kidney failure, or death. 
  • Combining Adderall or Adderall XR with drugs that affect serotonin can cause serotonin syndrome. Examples of these drugs include certain antidepressants, triptans for migraine, and opioid pain medications.
  • Drugs that affect an enzyme called CYP2D6 can increase Adderall levels in the body, which can also cause serotonin syndrome. Examples of these drugs include Wellbutrin (bupropion) and Cymbalta (duloxetine). 
  • Tricyclic antidepressants such as Elavil (amitriptyline) or Pamelor (nortriptyline) may increase levels of Adderall in the person’s system, which can worsen cardiovascular effects.
  • Lithium can decrease the effects of Adderall. 
  • Drugs that affect the urinary pH can affect the blood levels of amphetamines, as well as how they are eliminated from the body. For example, vitamin C causes acidity and can decrease blood levels of Adderall. 

These are just some of the potential drug interactions with Adderall and Adderall XR. Before taking one of these medications, tell your doctor about all the medications you take, including prescription drugs, over-the-counter medicines, vitamins, and supplements. 

Kidney and liver problems

Patients with kidney or liver problems should consult their healthcare provider before using Adderall or Adderall XR. Having a problem with the kidneys and liver can interfere with the body eliminating the medication, which could result in higher levels of amphetamine in the body. This could result in more serious potential side effects, which could be dangerous or life-threatening. 

Adderall withdrawal 

Adderall may cause dependence, which means that the body relies on the drug to function. Suppose you abruptly stop taking Adderall or Adderall XR or significantly decrease the dose, especially after taking this medicine for a long time or at high doses. In that case, you may experience withdrawal symptoms, such as:

  • A persistent state of uneasiness
  • Depression
  • Fatigue
  • Vivid and unpleasant dreams
  • Trouble falling asleep or staying asleep or excessive sleepiness
  • Increased appetite 
  • Slowed thinking or movements

To avoid Adderall withdrawal, take your medication exactly as prescribed by your doctor. Do not take more or less than your doctor prescribes. If you have any questions or concerns, notify your doctor right away. Do not abruptly stop taking the medication unless advised by a healthcare provider. 

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