What is the maximum recommended dose of Adderall (amphetamine and dextroamphetamine)?

Maximum Dose of Adderall

The maximum recommended total daily dose of Adderall (mixed amphetamine salts) is 40 mg per day according to the Physician's Desk Reference, though expert consensus allows for doses up to 40 mg daily in clinical practice, with rare exceptions going higher when clearly documented. 1

Standard Maximum Dosing Guidelines

• The PDR-established maximum is 40 mg total daily dose for amphetamines, which serves as the regulatory standard 1
• Expert practice guidelines often limit the upper range to 40 mg total daily dose of amphetamine when given in multiple doses throughout the day 1
• For adults and older adolescents, some patients may be treated with total daily doses of up to 0.9 mg/kg of amphetamine or 40 mg, whichever is lower 1

Weight-Based Dosing Restrictions

• Children weighing less than 25 kg should not receive single doses greater than 10 mg of amphetamine 1
• This weight-based restriction is critical to prevent excessive dosing in smaller children 1

When Higher Doses Are Considered

• Doses may rarely exceed the PDR-recommended upper limits, but this requires specific documentation 1
• If prescribing above 40 mg daily, clinicians must clearly document that symptoms could not be controlled at lower doses and that higher doses are not producing side effects (weight loss, blood pressure increase, or agitation) 1
• The patient should be monitored for signs of tolerance when using higher doses 1

Clinical Decision Point

If the top recommended dose (40 mg/day) does not provide adequate symptom control, more is not necessarily better 1

• A change in medication (switching to a different stimulant) or adding environmental/psychosocial interventions may be required rather than further dose escalation 1
• Approximately 70% of patients respond to either dextroamphetamine or methylphenidate alone, and nearly 90% will respond if both stimulants are tried 1

Dosing Schedule Considerations

• Adults may reach higher total daily doses because they need more frequent dosing to cover a longer day (not because they need higher individual doses) 1
• The typical adult dosing in clinical trials averages 54 mg daily administered in two divided doses, though this exceeds standard recommendations and was used in research settings 2

Important Safety Caveat

• Growth attenuation is more pronounced in children who require higher doses, particularly affecting both height and weight z-scores 3
• Cardiovascular monitoring (blood pressure, pulse) and growth parameters (height, weight) must be assessed at each visit when using any stimulant dose 1