Is it more effective for a patient taking 30mg of immediate-release Adderall (amphetamine and dextroamphetamine) per day to take the remaining 10mg as a single dose in the afternoon or to split it into two 5mg doses for a more extended effect?

From the Guidelines

For a patient taking 30mg of immediate release Adderall daily with 20mg (two 10mg tablets) in the morning, splitting the remaining 10mg dose into two 5mg doses taken a few hours apart in the afternoon would likely provide a more extended therapeutic effect. This approach can help maintain more consistent medication levels throughout the day and potentially reduce the "crash" that some patients experience as immediate release Adderall wears off. Immediate release Adderall typically lasts about 4-6 hours, so taking 20mg in the morning, 5mg in the early afternoon (perhaps around 1-2pm), and the final 5mg later (around 4-5pm) would provide more continuous coverage. However, the patient should be mindful not to take the final dose too late in the day as this could interfere with sleep. This dosing strategy should be discussed with the prescribing physician before implementation, as individual responses to medication vary, and the optimal dosing schedule depends on the patient's specific symptoms, daily routine, and how they metabolize the medication 1.

Some key points to consider when implementing this dosing strategy include:

• The patient's daily schedule and how it may impact medication adherence
• The potential for side effects, such as insomnia or anorexia, and how to manage them 1
• The importance of regular follow-up appointments with the prescribing physician to monitor the patient's response to the medication and make any necessary adjustments 1
• The potential benefits of using a consistent titration schedule and assessing drug response through regular evaluations of target symptoms and side effects 1

It is also important to note that individual responses to medication can vary, and the optimal dosing schedule may depend on the patient's specific symptoms, daily routine, and how they metabolize the medication. Therefore, it is crucial to work closely with the prescribing physician to determine the best course of treatment and to make any necessary adjustments to the dosing strategy. By taking a collaborative and individualized approach to medication management, patients can maximize the benefits of their treatment and minimize the risks of side effects or other adverse outcomes.

From the FDA Drug Label

DOSAGE AND ADMINISTRATION Amphetamines should be administered at the lowest effective dosage and dosage should be individually adjusted. Give first dose on awakening; additional doses (1 or 2) at intervals of 4 to 6 hours.

The patient is currently taking 30mg of immediate release Adderall per day, and has taken 20mg in the morning. To reach the total daily dose of 30mg, the patient needs to take an additional 10mg. It is recommended to take the additional 10mg in divided doses, at intervals of 4 to 6 hours, as stated in the drug label. Therefore, taking half of the tablet (5mg) and then another half tablet (5mg) a little while later may be a better option to get a more extended effect, rather than taking the full 10mg at once. 2

From the Research

Immediate Release Adderall Dosage

• The patient is currently taking 30mg of immediate release Adderall per day, with 2 10mg tablets taken in the morning 3.
• The question is whether it is better to take the full 10mg in the afternoon or to take half of the tablet (5mg) and then another half tablet (5mg) a little while later to get more of an extended effect.

Pharmacokinetics of Amphetamine

• Amphetamine is rapidly absorbed, with high absolute bioavailability, followed by extensive metabolism involving multiple enzymes 3.
• The Tmax for immediate release formulations is typically 2 to 3 hours, with a plasma T1/2 of around 7 hours in children and 10 to 12 hours in adults 3.
• There are several immediate-release formulations available, including d-AMP, dl-AMP, and mixed amphetamine salts 3, 4.

Extended Effect of Adderall

• Taking half of the tablet (5mg) and then another half tablet (5mg) a little while later may provide a more extended effect, as the drug is released in a more staggered manner 3.
• However, the optimal dosing strategy will depend on individual factors, such as the patient's weight, metabolism, and response to the medication 3, 4.
• There is no clear evidence to suggest that taking the full 10mg in the afternoon is superior to taking half of the tablet and then another half tablet a little while later 3, 4, 5.

Note

• Studies 6 and 7 are not relevant to this question, as they discuss unrelated topics, such as mepolizumab for COPD and epigenetic mechanisms of amphetamine, respectively.