A Comparison of the Effects
of Amphetamines
(Adderall etc.) and Methylphenidate (Ritalin etc.)
on Symptoms of Adult ADD
Marc D. Schwartz, MD
The Adult
ADD Center of New Haven
26 Trumbull Street, New Haven, CT 06511
Clinicians treating patients with ADD often have to decide which type of stimulant medication to prescribe, amphetamines (like Adderall, Dexedrine, and others) or methylphenidate (like Ritalin, Concerta, Focalin, and others. Vyvanse is an amphetamine type stimulant, but was not on the market when this study was done.) I created a questionnaire designed to see if there is a difference between the effects of these two types of medications on ADD symptoms and had 37 of my adult patients who benefited from treatment complete it.
All patients had taken one or both kinds of medication and had achieved optimal treatment results with at least one of them. Optimal results were defined as those achieved by slowly increasing the dose of the medication to the point where there was definite improvement in a patient's ADD symptoms but where a higher dose either did not achieve a better effect or caused unacceptable side effects. Patients who benefited from neither amphetamines or methylphenidate were not asked to complete questionnaires.
Each item in the questionnaire contained a statement about the effect of the medications, for example, helps you focus on details, reduces hyperactivity, etc. Patients scored items on a 6 point scale where 0 indicated the medication had no effect, 3 a moderate effect, and 5 a strong effect.
Results
Thirty seven patients completed 50 questionnaires. Twenty
four had achieved
optimal results after taking one type of medication: for twenty, this was AMP,
for four it was MPH. These patients took the questionnaire once.
Thirteen had been treated first with one medication, failed to achieve optimal results, then were switched to the other and did achieve such results. They completed a questionnaire for both medications after achieving optimal results with the second. One patient found neither medication on its own to be optimal and was treated with both simultaneously.
The Overall Effects of the Stimulants on Patient Who
Benefited from Treatment
An analysis was first carried out on all subjects'
questionnaires, regardless of which stimulant or stimulants they had taken. The symptoms found to be most affected by the stimulants were those which involved
executive functioning such as concentration, focus, task initiation, and
others (Table 1). A lesser beneficial effect was seen for hyperactivity
and impulsivity. Changes resulting from side effects, such as loss of
sleep, loss of appetite, and anxiety, were rated smaller.
Table
1 -
Average Effect of Stimulants ( Scale: 0 = No Effect to 5 =
Strong Effect )
37 patients, 50 questionnaires
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It should be kept in mind that these overall impressive results were obtained from patients who had, for the most part, benefited from using stimulants. Patients who benefited neither from AMP or MPH were not given the questionnaire. Still, a third of the questionnaires (13 of 37) were scored by patients who had not achieved an optimal result from one of the medications then had taken the other medication and had only then completed questionnaires for both medications.
Differences Between AMP and MPH
The profile of patients’ responses to AMP
and to MPH were similar, but there were differences. The following two
tables present the size of the differences. The first table lists the symptoms
that responded more to AMP and the second those that responded more to MPH.
The size of the difference between them is listed in the third columns. Items are
arranged with those items showing the greatest difference listed first.
Items for which the difference between medications was less than 0.3 were
not included in the lists.
Table 2 - Items Which Patients Scored AMP Higher Than They Scored MPH
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The effects of AMP were scored higher than those of MPH for most of the executive functions. However, it seemed to interfere with sleep a bit more than MPH.
As can be seen in Table 3 below, MPH failed to score higher than AMP on any executive function. However, it was scored higher for side effects including anxiety, agitation, and irritability. Paradoxically it had a slightly greater effect than AMP on helping patients sleep (and, as noted in Table 2, interfering less with their sleep) and in increasing relaxation.
Table 3 - Items Which Patients Scored MPH Higher Than They Scored AMP
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Discussion
On the basis of these finding, it appears
that AMP medications were generally more effective than MPH medications for
treating ADD executive function
symptoms. In addition, they caused less anxiety, agitation, and irritability. However,
they tended
to interfere with sleep more than MPH. In fact, MPH was reported to
help the average ADD patient in this study sleep better.
Conclusion
The results of this study suggest that, except for those ADD patients with
sleep problems, AMP medications are a better first treatment option than are
MPH medications.