Sunday, October 26, 2008

The Effectiveness of Adderall as an ADHD Medication

Adderall as an ADHD stimulant medication

Adderall is one of the most popular (and currently one of the most "trendy") types of ADHD medication. As a stimulant drug, Adderall is chemically and functionally similar to other ADHD stimulants including Ritalin, Dexedrine, Concerta or Focalin. However, while most of these medications contain either one or two compounds, Adderall technically contains eight. It is a combination of four different types of amphetamines (in the salt form) and their chemical "mirror images".

A bit of a side note on "mirror images" and drug chemistry: For reference sake, consider your left and right hands. They are identical in structure, but mirror images of each other. This mirror image effect plays an important role in pharmacology, and separation of the two mirror images can be extremely important. For example, one mirror image of the pregancy drug Thalidomide was used to treat morning sickness, while the other mirror image was linked to birth defects. Fortunately this grave difference between mirror images is not seen with ADHD stimulant medications. Some ADHD drugs, such as Dexedrine or Focalin only have the "right hand" form, which have different (and often more potent) properties than the "left hand" form. Nevertheless, both mirror images of each of the 4 different amphetamines are seen in Adderall, making it a combination of 8 distinct compounds.

Returning to the main topic, this post will be focusing on the overall effectiveness of the ADHD stimulant Adderall. This information comes from a large review done in 2002 in the Journal of Attention Disorders by Faraone and Biederman. A short synopsis of the orignal article on the medication Adderall and ADHD can be seen here. Please note that these studies focused primarily on the effectiveness of Adderall vs. a placebo and not Adderall vs. other ADHD medications. There actually are studies out there comparing stimulant medications for ADHD, which will be covered soon in later posts.

Also, the form of Adderall used for this review was the standard release version. No slower/extended release (Adderall XR) analyses were covered. Given the time of this publication, Adderall XR data was still scarce. Since 2002, this has changed, and additional insight will be covered in future posts. For now, I will be highlighting some of the main findings of the article below:

  • Adderall outperformed the placebo in a statistically significant manner for both academic and behavioral improvements. These improvements were seen by all three monitoring groups: parents, teachers and clinicians, and were consistent, even among the several different ADHD rating systems used by the three groups.
  • Additionally, consistency was seen with regards to the effectiveness of Adderall regardless of whether the stimulant medication was administered via fixed-dose (a set dosage for test subjects) or via "best-dose" (the dosing was tailored to the individual by considering the size and gender of the individual, history of other medications taken and the responsiveness to these medications). This suggests the possibility that Adderall may have a more flexible range of effective dosing than most other ADHD drugs.
  • The study identified that there is often an inherent clinical bias in reporting the effectiveness of medications because "success" stories in which ADHD medications are effective are naturally published more often than for "failed" studies. A correctional factor (described in the article) was used to counteract this implicit effectiveness bias. Just keep in mind that published results are often not a full representation of data from the full spectrum of studies.
  • Adderall treatment (at various doses) appears to be almost as effective in treating aggressive behaviors as in treating ADHD. This spells good news for individuals with ADHD who also exhibit potentially violent or overly-aggressive behavior.
  • Although parents, teacher and clinicians all saw improvements with regards to ADHD across the board, the highest levels of measured improvement was typically seen by those in the medical profession. Parent and teacher evaluations showed similar levels of improvements with respect to each other, but their results were often not as pronounced as those done by clinicians.
  • In addition to clinician reports giving higher ratings, the mode of measurement for ADHD symptom improvement was also a factor. Symptom ratings scales, refer to a reduction in negative symptoms associated with the disorder. They do not take into effect things such as improvements in school or improvements in social skills, as these are more difficult to monitor as measurable "symptoms".
  • By contrast, global ratings also incorporate factors in addition to the symptom ratings. In addition to measuring levels of "sickness" like symptom ratings, global ratings measure more degrees of "wellness", such as the social or academic improvements mentioned above. As a result, global ratings typically offer a wider spectrum and offer a more complete and detailed portrait of improvements following modes of treatment for ADHD. Not surprisingly, due additional improvement categories which can be measured, global ratings typically result in higher rating scores of medication effectiveness than do ADHD symptom studies.
  • Based on the layout and distribution of the data, and the overall high level of agreement in the results of multiple unrelated studies, the authors of the article concluded that additional studies on the topic of Adderall medication vs. placebo are unlikely to refute these results.

These results support the idea that ADHD treatments with Adderall are statistically superior to controls (i.e., it is highly unlikely that improvements along the spectrum of undesirable behaviors and effects of ADHD are due to the "placebo effect"). As a result, it is apparent that Adderall has solidified its place as a valid and viable treatment option for ADHD.

Nevertheless, we must now begin to focus on the overall safety of this ADHD drug, and how Adderall stacks up against other ADHD stimulant medications such as Ritalin, Focalin, Concerta, or Dexedrine. Please check for more posts addressing these two key areas in the near future.