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Medications To Improve Cognitive Functioning in Individuals with Traumatic Brain Injury

Dr. Sam Goldstein

Complimentary Service of the Neurology, Learning and Behavior Center

The Neurology, Learning and Behavior Center provides multi-disciplinary, clinical and forensic assessment, case management, trial consultation and treatment services for children and adults with brain injury and dysfunction, Attention-Deficit Hyperactivity Disorder, language disorders, learning disability, developmental delay, emotional disorders and adjustment problems. The Center is dedicated to the provision of treatment services.

MEDICATIONS TO IMPROVE COGNITIVE FUNCTIONING IN INDIVIDUALS WITH TRAUMATIC BRAIN INJURY

There has been a dramatic improvement in the care and treatment of individuals with brain injury in the past twenty years. Coincidentally, over the past fifteen years researchers and clinicians working with individuals recovering from traumatic brain injury (TBI) have begun to examine the possible role various classes of medication may play in either accelerating recovery or providing compensation for cognitive impairments. However, research on the use of medications to improve cognitive functioning continues to be in its infancy. Neurobehavioral deficits involving attention, cognitive efficiency, memory, reasoning, judgment and emotional regulation represent the most challenging problems in rehabilitation.

Although there is some substantive research suggesting that certain classes of medication may accelerate cognitive recovery or improve cognitive functioning in individuals with TBI, the data is inconsistent. Anecdotal reports and single case studies continue to serve as a primary foundation upon which care providers make decisions today to use these medications. A framework for making decisions about the use of these medications still remains to be developed, including the choice of medication versus localization of injury, time since injury, types of problems, and environmental variables.

Although a number of classes of medication have been studied, by far the stimulants, Ritalin®, Dexedrine® and Cylert® have been of greatest interest. Methylphenidate, marketed under the trade name Ritalin, is used to treat millions of children with Attention Deficit Hyperactivity Disorder (ADHD). Though stimulants certainly can produce side effects their benefits usually outweigh liabilities. Stimulants increase frontal lobe activity in individuals who have difficulty developing self-regulation and self-control. Though problems in the frontal lobe, particularly the right pre-frontal cortex of people with ADHD may differ from the frontal lobe dysfunction that occurs post TBI, it is likely there is sufficient similarity between these two sets of problems to expect that stimulants would be of benefit in treating these symptoms. Ritalin enhances cognitive performance, including working memory and executive function. Psychostimulants appear to be a reasonable choice for treating certain types of mood, behavioral and cognitive symptoms following TBI. Particular problems related to faulty or inefficient self-control appear to respond best. An increasing number of studies with children and adults suffering from TBI utilizing stimulants have demonstrated their therapeutic value. Still, however, some studies do not find clinically significant results.

Although anti-convulsants are routinely used to prevent or suppress post traumatic epilepsy, these medications have not been found to improve cognitive functioning. In fact, just the opposite. As I discussed in Legal Update #2, these drugs may control epilepsy at the expense of decreasing self-control.

Drugs that impact the dopamine system in the brain, including Amantadine®, Bromocriptine® and Sinemet®, may improve some aspects of cognitive functioning but at the expense of others. Medications such as the anti-hypertensives, Tenex® and Clonidine®, have also been reported to have mixed results in the treatment of attentional problems. Problems related to apathy and difficulty with initiation may respond to these preparations as well as to serotonin based anti-depressants such as Prozac® and Zoloft®. Anti-Parkinson medications such as Sinemet® has been found to improve emotional and behavioral deficits in individuals with moderate to severe TBI.

The newer Alzheimer’s medications, Aircept® and Tacrine®, have also been used increasingly with TBI patients. These medications were designed to enhance cholinergic functioning. There is a small but increasing body of research supporting that medications restoring cholinergic function in individuals with TBI enhances cognitive performance.

There has also been interest in over the counter preparations such as ginko biloba. The belief is that these natural substances can produce mild improvements in cognitive functioning. However, definitive studies still remain to be completed.

An increasing body of research suggests that many medications can alleviate cognitive dysfunction following TBI and may in fact enhance recovery. As far as I am aware, however, a large scale, multi-site study examining the use of these medications in populations of individuals with TBI has yet to be undertaken. Therefore it is difficult to know whether using these medications today should represent the standard of care for TBI patients. Many children and adults with TBI whom I follow benefit from these medications. Although there is no precise science to adjusting these medications, I have observed a number of individuals across all age ranges respond exceptionally well, particularly to Dexedrine and Methylphenidate following TBI. For some the medicine is used acutely. For others, however, the medicine becomes a long-term treatment compensating for loss of and enhancing self-regulation.

If in fact, as an emerging body of literature suggests, these medications can dramatically improve the daily and future lives of individuals with TBI, attorneys on both sides of the table must be aware of them. They will become an important variable in determining maximum medical improvement. When not prescribed or when a client doesn’t follow a recommendation for their prescription, outcome and long-term functioning may be significantly compromised.

Selected References

Bleiberg, J., Garmoe, W., Cederquist, J., et al. (1993). Effects of Dexedrine on performance consistency following brain injury. Brain Injury, 6, 245-248.

Kraus, M.F. & Maki, P. (1997). The combined use of Amantadine and L-Dopa/Carbidopa in the treatment of chronic brain injury. Brain Injury, 11, 455-460.

LeBars, P.L., Katz, M.M., Berman, N., et al. (1997). A placebo controlled double-blind randomized trial of an extracted ginko biloba for dementia. Journal of the American Medical Association, 278, 1327-1332.

Massagli, T.L. (1993). Carbomazepine, Pheneytoin and Valporate Acid. Implications for use in traumatic brain injury. Archives of Physical Medicine and Rehabilitation, 74, 224-225.

Schneider, W.N., Drew-Cates, J., Wong, T.M., et al. (1999). Cognitive and behavioral efficacy of Amantadine in acute traumatic brain injury: An initial double-blind placebo controlled study. Brain Injury, 13, 863-872.

Taverni, J.P., Seliger, G., & Lichman, S.W. (1998). Donezepil-mediated memory improvement in traumatic brain injury during post acute rehabilitation. Brain Injury, 12, 77-80.

Whitlock, J.A. (1999). Brain injury, cognitive impairment and Donepezil. Journal of Head Trauma Rehabilitation, 14, 424-427.

Whyte, J., Hart, T., Schuster, K., et al. (1997). Effects of methylphenidate on attentional function after traumatic brain injury: A random placebo controlled trial. American Journal of Physical Medicine and Rehabilitation, 76, 440-450.

Williams, S.E., Ris, M.D., & Ayangar, R. (1998). Recovery in pediatric brain injury: Is psychostimulant medication beneficial? Journal of Head Trauma, 13, 73-81.