Lisdexamfetamine to Dexamphetamine Conversion Guidelines

Introduction to Conversion

The American Academy of Child and Adolescent Psychiatry recommends starting with 70-75% of the calculated equivalent dose when switching from lisdexamfetamine to immediate-release dexamphetamine, then titrate by 2.5-5 mg increments weekly based on response 1, 2

For a patient on lisdexamfetamine 30 mg, the American Academy of Child and Adolescent Psychiatry suggests starting dexamphetamine at 7.5 mg total daily, split as 2.5 mg TID or 5 mg BID 1, 2
For a patient on lisdexamfetamine 50 mg, the American Academy of Child and Adolescent Psychiatry recommends starting dexamphetamine at 10-12.5 mg total daily, split as 5 mg BID or 5 mg TID 1, 2
For a patient on lisdexamfetamine 70 mg, the American Academy of Child and Adolescent Psychiatry suggests starting dexamphetamine at 15 mg total daily, split as 5 mg TID or 7.5 mg BID 1, 2
The American Academy of Child and Adolescent Psychiatry advises allowing at least one week between dose adjustments to properly evaluate response 1, 2
Titrate in 2.5-5 mg increments based on symptom control and tolerability, with a maximum recommended daily dose of 40-50 mg for dexamphetamine 1, 2, 3

Monitor blood pressure and pulse at baseline and with each dose adjustment 2
Weigh the patient at each visit to monitor for appetite suppression 2
Approximately 70% of patients respond to a single stimulant type, but nearly 90% respond if both amphetamine and methylphenidate are tried 1, 2
For children weighing less than 25 kg, single doses should generally not exceed 15 mg 1, 3
Do not give late afternoon or evening doses—last dose should be before 2-3 PM to minimize sleep disturbances 2
Do not exceed maximum recommended doses (40-50 mg/day) if inadequate response occurs—instead reassess diagnosis and consider switching to methylphenidate or non-stimulant alternatives 1, 2, 3