'PHYSICAL DEPENDENCE' ON CANNABIS NOT DOCUMENTED

In response to Dr. Timmen Cermak ("What doctors say about marijuana,"
Insight, Aug. 22), I am not questioning the fact that a small
minority of cannabis users can develop a "problem use" or even some
symptoms of withdrawal upon the cessation of cannabis use.

The same, I am sure, would happen with cessation of caffeine use. I
question the validity of "physical dependence" on cannabis, because
such dependence can be diagnosed only if there is a documented
physical withdrawal syndrome, such as consistent changes in vital
signs, pupil sizes, increased bowel sounds, fever and the like.

I worked as a program physician in methadone clinics for years, and
as you know very well, all these symptoms of "discomfort" are
absolutely not enough to put a patient on methadone. There must be
physical signs of dependence, not just some "non-specific discomfort."

Or, let's take an alcohol withdrawal. Surely, no one will question
the physical nature of alcohol dependence after having seen a patient
going into "DTs."

I continue to strongly believe that this constellation of dependable
and reproducible physical signs of cannabis dependence are not
documented, so we are not entitled to postulate the existence a true
physical dependence on cannabis/marijuana.

Leonard Krivitsky, M.D., Philadelphia