Tuesday, September 9, 2008

Why We Shouldn't Blame Benzos

Sometimes I hear from well-meaning medical practitioners that methadone is unfairly maligned as it is blamed for so many deaths. Benzodiazepines, these doctors argue, are to blame for so many methadone poly-drug deaths. Benzodiazepines are the real killers. I don't buy it. While admittedly the dangers of combining benzodiazepines with methadone are well-known in the medical community, many people dependent on benzodiazepines continue to use them for years and years, without dying. In addition, benzodiazepines are highly addictive, and withdrawal can lead to fatal seizures. The New York Times recently reported:

"A majority of victims also used large quantities of alcohol or benzodiazepine sedatives but few would have died without an opioid as the primary culprit. 'You can take a lot of benzodiazepines without dying,' said Dr. Charles E. Inturrisi of Weill Cornell Medical Center, who said they strengthen the depressive effect of methadone."

What I am concerned about more than all the people using benzodiazepines, is all the doctors prescribing methadone to the people using benzodiazepines. A patient with a long-standing history of benzodiazepine use should not be started on methadone until the physician confirms the patient is benzodiazepine-free.

Why People Die From Methadone

There has been a debate for some time about why people are dying from methadone toxicity. I don't mean why methadone the drug causes deaths-- that is something that is well-understood in the medical/scientific community, given the highly variable half-life among individuals and the risks to those who are opiate naive. What I mean is that the medical community wants to blame deaths on the methadone clinics andn the methadone clinics want to blame the physicians, and when push comes to shove, they all would rather blame it on diversion. Diversion of methadone from those legally prescribed it is a problem, and street use of methadone is apparently responsible for thousands of deaths. That should make sense to us. But remember that if diversion is causing deaths, then the physicians prescribing it to patients who then lose it, sell it or have it stolen bear a large part of the responsibility for the methadone on the street. But as much as the educated and employed want to blame the "addicts" for this epidemic, many deaths are attributable not to street use, but to use as prescribed by a physician. Eric Eckholm with the New York Times recently reported: "Misuse by abusers was first seen as the problem, but now, said Dr. H. Westley Clark, director of the Center for Substance Abuse Treatment of SAMHSA, 'We know that a significant share of the methadone deaths involve doctors making well-intended prescriptions.'" That is what is so tragic about methadone deaths in the U.S. The following study from the Jouornal of Forensic Sciences found over 48% of methadone deaths werew attributable to well-intended presciptions by doctors.

Methadone toxicity fatalities: a review of medical examiner cases in a large metropolitan area.
J Forensic Sci. 2007 Nov;52(6):1389-95.
Shields LB, Hunsaker Iii JC, Corey TS, Ward MK, Stewart D.
Office of the Chief Medical Examiner, Urban Government Center, Louisville, KY 40204, USA.
Over the past several years, Medical Examiners in Kentucky and around the nation have observed a dramatic rise in drug intoxication deaths involving the prescription medication methadone. This documented rise in methadone-related deaths requires a better understanding of methadone's pathophysiology and the ways it contributes to significantly increase morbidity and mortality. This study reviews 176 fatalities ascribed to methadone toxicity by the Office of the Chief Medical Examiner in Kentucky between 2000 and 2004. Postmortem toxicological analysis recorded a more than 10-fold increase in methadone toxicity fatalities, rising from 6 cases in 2000 to 68 cases in 2003. Of the 176 methadone-related fatalities, methadone was the only drug detected in postmortem blood and urine toxicological analyses in 11 (6.25%) cases. The mean methadone blood concentration of all 176 cases was 0.535 mg / L (0.02-4.0). The following psychoactive medications were detected: antidepressants (39.8%), benzodiazepines (32.4%), and other opioids in addition to methadone (27.8%). Cannabinoids were detected in 44 (28.4%) cases and cocaine or metabolite in 34 (21.9%) cases. Of the 95 cases with a known history of methadone use, 46 (48.4%) involved prescription by private physician. The interpretation of blood methadone concentrations alone or combined with other psychoactive drugs requires consideration of the subject's potential chronic use of and tolerance to the drug. A thorough investigation into the practices of procurement and use/abuse of methadone is essential to arrive at the proper designation of the cause of death.