teve is a
17-year-old with a scraggly goatee, a propensity to wear
Grateful Dead T- shirts and a strange medical complaint. A few
months earlier, in response to symptoms of clinical depression,
I had placed him on Prozac, a selective serotonin reuptake
inhibitor, known as S.S.R.I.
Although he no longer complained of sadness, poor
concentration and boredom, the problems that gave occasion to
his being prescribed Prozac, he was now experiencing frequent
disturbances of color and occasional moments when people he was
looking at transformed into cartoonlike figures.
Unfortunately, I paid too little attention to his complaint
and reflexively reached for my prescription pad to switch his
medication from Prozac to Zoloft, the equivalent of switching
from Coke to Pepsi, hoping that a different S.S.R.I. might solve
the problem. Because these episodes weren't particularly
distressing to Steve, we agreed to see each other within a
month. But my therapeutic intervention accomplished nothing,
and, again, I switched him to still another S.S.R.I.
At a later visit, Steve admitted that until seven months ago,
when he was caught selling pot at his high school, he had been a
"garbagehead." In teenage parlance this means that whatever drug
he came in contact with — alcohol, marijuana, Ecstasy,
over-the-counter cold remedies, you name it — Steve consumed it,
and often daily.
But for the past few years, his drug of choice was LSD. Until
he was arrested and required to enroll in a strict drug
abstinence program, Steve tripped weekly. When we met, he had
been clean for about five months but the episodes he was
complaining about reminded him of "when I was tripping on
acid."
Doctors who treat adolescents deal with drug abuse almost as
often as other pediatricians encounter ear infections; but
Steve's LSD use was particularly troubling because, like many
physicians, I had little experience recognizing or treating the
problems that can result from it. Indeed, before meeting Steve,
LSD was more of historical interest to me than practical or
clinical value: a quaint relic from the flower-power era of the
late 1960's and early 70's.
As a matter of fact, LSD is again emerging as a serious
concern to pediatricians and parents alike. According to the
Monitoring the Future Study conducted by the University of
Michigan's Institute for Social Research, the rates of lifetime,
annual and current use of LSD among 8th, 10th and 12th graders
have gradually increased since 1990.
Although LSD use reached its peak in 1996, during 1999, about
12 percent of American high school seniors used LSD at least
once and more than 8 percent of them used it at least annually.
More alarming, about 3 percent of these young adults tripped
monthly.
There are many reasons to avoid LSD, but one of the most
distressing side effects that can result from its chronic abuse
is the flashback syndrome. Flashbacks are recurrent
hallucinatory episodes that are not associated with the presence
of the drug in the brain and may occur months to years after
stopping its use. I wondered if this phenomenon might explain
Steve's problem.
In the weeks that followed I began to inquire more closely
about the LSD use of other patients I treated for depression
with S.S.R.I.'s. Soon enough three more teenagers admitted to
having used LSD and while none of them had used the hallucinogen
for many months, all began to experience flashbacks only after
initiating treatment with an S.S.R.I. agent. One patient, an
18-year-old named Lisa, described a few flashbacks that, unlike
Steve's almost humorous experiences of watching his teachers
transform into Pokemon characters, were upsetting and
debilitating. When I queried these teenagers why they had not
complained to me before about the flashbacks, each had the same
response: you never asked!
Concerned about these four teenagers, I left my clinic one
evening and headed straight for the stacks of the medical
library. When armed with a novel clinical experience this can be
one of the most exciting places on earth for a doctor to conduct
a game of medical detective. Before the night was over, a
Eureka-like moment was to be had.
Serotonin reuptake inhibitors, as their name implies, prevent
the reabsorption of this neurotransmitter from the synapse, the
gaps between two neurons that rely on chemicals like serotonin,
dopamine and norepinephrine to communicate with one another.
Although the exact mechanism for depression remains unclear,
many students of psychiatry say a central role may be played by
abnormally low levels of serotonin in the brains of depressed
people. This theory is supported by the miraculous impact
S.S.R.I.'s have had on millions of Americans who suffer from
what the ancient physicians called melancholia.
Excitedly leafing through the literature on LSD, I learned
that the hallucinogen not only increases serotonin levels in the
brain, it also has a special affinity for many of the same
neuroreceptors. The likely mechanism, then, for my patients' new
onset of flashbacks was that the S.S.R.I. agents I prescribed
were not only yielding an increased concentration of serotonin
in their central nervous systems but were also overstimulating
their serotonin receptors. Within months of discontinuing the
S.S.R.I.'s, all of the teenagers' flashbacks ended but could
return unpredictably. Happily, these teenagers all, thus far,
remain clean and sober and free of depression.
After consulting with several pharmacologists who specialized
in the effects of LSD on the brain, we presented these four
teenagers' cases to my colleagues and ultimately published their
cases in The Journal of Pediatrics to alert others who care for
adolescents with a history of both depression and LSD abuse. But
for me these exercises were more a lesson in humility than a
proud accomplishment.
Steve and other patients who experienced flashbacks, perhaps
as a result of prescriptions, taught me two valuable clinical
lessons: a simple solution to a complex problem has the
potential to worsen things; and, often a patient hands you the
correct answer but the key is figuring out the right
question.
