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An Update On
Medications Used In The Treatment Of Attention Deficit Disorder
by John Ratey, M.D.
The use of medication to treat adults with Attention Deficit Disorder
is a happy intersection of neuroscience and availability of a drug
to fit the supposed problem. To the best of our knowledge the major
problem in the attention system in the brain of the person who has
the diagnosis of ADHD, or of ADD without the H, is a difference
in their dopamine system. Current research shows that there may
be as many as 13 different genes that vary from the so-called normal
genes that are involved in making up what we call the attention
deficits. These genes, which are called alleles as they are alternatives
to the most common variety of gene, are mainly involved with the
dopamine system. This is reflected in the fact that there is not
enough dopamine around to support the system to work in a consistent
and predictable manner.
Thus the treatment for ADHD/ADD rests on the drugs we know as those
which affect the dopamine system: the antidepressants, the stimulants,
and precursors that may boost the effectiveness of dopamine. While
most neuroscientists and neuroscience wannabes are hesitant to reduce
anything to a simple equation or catch phrase we might be on fairly
firm ground in saying that attention problems may be seen as a dopamine
deficiency. Thus the job of medication is to correct this deficit
and its associated problems like anxiety, depressed and demoralized
moods, overactive startle response, and the many problems with aggression
and addictions.
The use of stimulant medications is still the easiest and most
accurate route and the one that has proven to be the most efficacious
for the greatest number of people with the diagnosis of ADHD. Contrary
to popular wisdom and media perception, they are among the safest
drugs. For instance, the only longitudinal studies to date on adolescents
show that rather than being a stepping stone to addiction, the one
robust finding is that those ADHD adolescents who took Ritalin were
less likely to have a substance abuse problem at the end
of their teens and early twenties. For the adult population this
is also true. Most of the patients who are treated with stimulants
do very well and have little need to escalate the dose once the
proper level has been established. In fact, given the pain that
monthly prescriptions are for both physician and patient, I am keenly
aware of the fact that most adult patients use less and less stimulant
as time goes on rather than any creep upwards in dose which some
fear may be the quick step to problems with addictions.
The stimulants are usually the first choice as I have stated because
they have a positive effect almost 90% of the time and have fewer
side effects than any of the antidepressants. We are still confined
to using three types of stimulants: methylphenidate or Ritalin,
amphetamine and its brothers and sisters known to most as Dexedrine
or Adderall, and pemoline or Cylert. All these medications act by
affecting the levels of dopamine at the synapse. Some release dopamine
directly, Ritalin and Dexedrine act also to block the reuptake mechanism,
and they also act to block some of the metabolic enzymes that hang
around the synapse to gobble up loose dopamine.
Pemoline (Cylert) is a long acting medication that takes a while
to get to its therapeutic action and thus it does not have an immediate
effect like Ritalin or Dexedrine. It also has a saga attached to
its use of reported deaths due to liver failure. While the circumstances
and the real incidences of the number versus the chance effect is
yet to be fully detailed, as of yet it is considered controversial
as a first line treatment and recommended only as a second line
treatment by the FDA. Abbot Pharmaceuticals, the
company that produces Cylert, has not been aggressive in countering
the complaints and perception of the risk so that its use has dropped
off and Cylert probably will continue to be a second line choice.
It is unfortunate as this is truly the only all-day stimulant we
have available. Clinical experience shows that the longer the drug
acts, the better and the closer it is to producing a normalized
attention span, a predictable state of consciousness, and a stable
inner core to interact with the environment.
I quickly realized when treating patients that the longer the medication
worked the better. One of the most important therapeutic actions
is to try and produce consistency in our patients brain functions.
We try to help them achieve a stable mood and attention function
so that they begin to realistically anticipate that each day will
be like the next. The argument that the shorter acting compounds
offer more control over the attention system seems ludicrous since
for most patients the most troubling aspect of using stimulants
is the second or third dose, which they often forget. One of the
major problems in the ADDer is the ability to remember and plan
- so that the need to take another pill at a certain time, and to
be aware of the decreasing effectiveness of the medication as it
wears off, is a huge problem. Secondly, the up and down effect of
the shorter acting agents can add to the disruptive inner state
that the patient has dealt with all of his or her life. The shorter
acting stimulants thus present problems with not getting to what
I see as an important goal and benefit of any treatment - stability
and predictability of attention, mood, and behavior.
Ritalin for all the media coverage has been the most used by most
physicians but I see it as the second line drug, because of its
short action and because in my experience it has more side effects
than Dexedrine or Adderall. It seems to affect the body more than
amphetamine and gives people more muscle discomfort, tenseness and
the hibbey gibbeys. Its one advantage that is certainly intangible
is that for some it has more of a motivational edge, driving people
to do their work with a bit more intensity. But like many other
aspects of medicine this is a double-edged sword and can lead some
to complain of robotic effects, lack of flexibility, workaholic
tendencies and the like. Ritalin lasts from 1 ½ to 3 hours in most
people, and the SR preparation is no bargain in that it only seems
to last another hour or so. Furthermore the idea that people are
getting 20 mg of the slow release preparation is troubling as Paul
Wender M.D. long ago studied the Slow Release form and found that
this 20 mg pill only gave the equivalence of 7.5 mg of the quick
release preparation.
The amphetamine compounds are longer acting, usually lasting anywhere
from an hour to two hours longer. The longer acting preparations
like Dexedrine spansules and Adderall definitely seem to work upwards
of 4-6 hours for most patients. But as with any drugs that affect
the brain, there is no cookbook as the variety in absorption, distribution,
and metabolism system in each individual makes it impossible to
predict how each person will handle a given drug. Then you have
the fact that the target organ here is the brain, arguably the most
complicated structure in the universe and vastly different from
one person to another. Therefore, despite our need to reduce and
control symptoms we have to accept the fact that dosage, effectiveness,
and side effects will vary greatly. I have written that Dexedrine
is "softer" than Ritalin and I still find that to be the
case. The amphetamine preparations have less side effects, and their
long acting preparations are definitely the real item. The difference
between Adderall and Dexedrine spansules in most patients is minimal.
However, there are some who have a much better response on Adderall
than on long acting Dexedrine. The reverse is also true but to a
much lesser extent.
I am a big fan of using the antidepressants with patients as they
have the 24 hour action that I believe is so critical. The problem
is that they work less well and in a smaller percentage of patients
than the more popular stimulant medications. First there are the
tricyclics - they have been around for more than 30 years and have
proved to be invaluable and relatively safe as a treatment for ADD
and related problems. I traditionally use low doses of desipramine
(10-40 mg/day) in many adult patients as this has very low toxicity
and is effective in about 30% of patients. Joseph Biederman M.D.
and colleagues have written much about the use of desipramine, nortriptyline,
and imipramine in adults and children and have found them to be
effective about 50% of the time, though they use higher doses approaching
what is recommended as treatment for depression (150-200 mg/day).
There is controversy over the use of desipramine in children as
to its side effect on the heart's conduction system. There are a
number of reports of sudden death from cardiac arrhythmia in children
using desipramine. The irritant effect on the heart conduction pathway
is reduced after adolescence. As in the case of Cylert, if one uses
statistics to look at the actual numbers of untoward incidences
of dire problems one would conclude that these drugs are not the
cause of the problem. However the availability of decent alternatives
seems to make the fears carry more weight and make the tricyclics
second line treatments in children, and for Cylert second line treatment
in adults as well. These drugs affect the norepinephrine and the
dopamine system in the brain so again they act to counter the suspected
dopamine deficit.
Wellbutrin (bupropion) came out as a hoped for wonder drug that
was touted as the replacement for Ritalin. It blocks the reuptake
of dopamine and should be an effective alternative to the stimulants.
It is long acting, now there is a slow-release preparation, and
it is was claimed to have fewer side effects than the tricyclics.
Unfortunately, the effectiveness that we find in the clinical setting
is not as happy as we had predicted and hoped for. It works well
in about 50% of cases but has many more side effects than any of
the previously mentioned choices. For use as an antidepressant,
Wellbutrin typically is used in doses of 300-450 mg/day. To treat
ADD the dose varies greatly and I have found that the new slow-release
preparation marketed for smoking cessation (another dopamine problem)
has fewer side effects and may be easier for patients to use, though
effectiveness is still very variable.
Both of these antidepressants can be used with the stimulants and
synergistically they may help overcome side effects and deficiencies
of each of the agents if used separately. For instance, many people
experience the rebound effect of Ritalin and Dexedrine whereby the
person notices a huge return and worsening of their symptoms as
the stimulant is wearing off and being metabolized out of the system.
The addition of an antidepressant which acts throughout the day
may help cushion this rebound effect. In like manner, the targeted
use of the stimulant while the person is on the antidepressant sharpens
the attention and focusing when it is necessary.
The newer antidepressant Effexor which is used in low doses, ½
of a 37.5 mg pill twice daily, is useful for some patients. Higher
doses often leads to unnecessary side effects, and there is a problem
for some in withdrawal of the drug when the trial is finished. Remeron,
the new antidepressant on the block, is again mainly a dopamine
and norepinephrine acting agent. A problem with Remeron is that
most people cannot wake up easily if they take the medicine. Without
a doubt this is the best sleeping agent I have ever used over the
years but the dose has to be low, low, low.
In summary, we have a number of medications which are proven effective
in the treatment of Attention Deficit Disorders. There are newer
medications being developed and undergoing clinical testing, including
a long acting 10-hour formulation of methylphenidate. We should
always keep in mind the huge variability between individuals as
to how they respond to a particular medication, dosage, or drug
interaction. We should also keep in mind that medication management
of ADHD is a crucial part of a comprehensive treatment plan, but
may not be enough in itself for most ADDers. Medication should be
accompanied in most cases by education, behavioral therapies which
address developing better coping skills, and ADD coaching.
About the author:
John Ratey, M.D., is an assistant professor of psychiatry at Harvard
Medical School. He practices psychiatry in the Boston area. He is
the author of Shadow Syndromes, and the co-author of Driven
To Distraction and Answers To Distraction. His new book
coming out in the Spring of 1999 is called The Users Guide
To The Brain. Dr. Ratey may be reached via e-mail at jratey@tiac.net
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