From the Guidelines
Adderall XR typically works for about 10-12 hours after taking it, as indicated by the most recent and highest quality study available 1. This extended-release formulation contains mixed amphetamine salts in two types of beads - one type releases immediately while the second type dissolves slowly to provide prolonged effects throughout the day. The medication is usually taken once daily in the morning, eliminating the need for multiple doses throughout the day. Individual responses may vary based on metabolism, body weight, and other medications being taken. Some people might experience effects for slightly shorter or longer periods. The extended duration of action occurs because the medication's special capsule design allows for gradual absorption in the digestive system rather than all at once. If the medication seems to wear off too quickly or last too long, it's essential to discuss this with your healthcare provider who may adjust your dosage or recommend a different formulation. Never adjust the dose yourself or take it later in the day as it may interfere with sleep. Key factors to consider when prescribing Adderall XR include its potential benefits, such as improved attention and reduced impulsivity, as well as potential adverse effects, including decreased appetite, sleep disturbances, and increased blood pressure and pulse, as noted in recent studies 1. Regular monitoring of pulse, blood pressure, height, and weight is recommended when prescribing psychostimulant medication, including Adderall XR 1. Additionally, consideration of the patient's individual needs, symptom profile, and potential comorbidities is crucial in determining the most appropriate treatment approach 1.
From the FDA Drug Label
Pharmacokinetics ... The average plasma T1/2 was similar for both the tablet and sustained-release capsule and was approximately 12 hours. The duration of action of Adderall (amphetamine and dextroamphetamine) XR is approximately 12 hours based on the plasma half-life (T1/2) 2.
- The plasma half-life is the time it takes for the concentration of the drug to reduce by half.
- This information is relevant to the sustained-release formulation of the drug.
From the Research
Duration of Action of Adderall XR
- The duration of action of Adderall XR (amphetamine and dextroamphetamine) is approximately 12 hours, as stated in studies 3, 4.
- This extended-release formulation provides a single-daily dose for the treatment of attention deficit hyperactivity disorder (ADHD) in children, adolescents, and adults.
- The 12-hour duration of action is achieved through a two-stage delivery system, which includes immediate-release and delayed-release pellets of mixed amphetamine salts 3, 4.
- The efficacy and safety of Adderall XR have been established through clinical studies in various populations, including school-age children, adolescents, and adults 3, 4, 5.
- While other studies have investigated the efficacy and duration of action of other medications, such as Concerta methylphenidate 6, and the bioavailability of Adderall XR formulations 7, the specific duration of action of Adderall XR remains consistent at 12 hours.