Street Cocaine Compromises Immune System

October 3, 2011

Here’s another reason not to abuse cocaine: Suppliers frequently cut the drug with a substance used to deworm livestock that can devastate the human immune system.

by Olivier Uyttebrouck
ABQ Journal

Researchers in New Mexico were among the first to warn in 2008 that the veterinary drug levamisole might be linked to an illness that leaves the body unable to fight infections.

“Many of these patients come in with pretty severe infections,” said Dr. David Czuchlewski, a professor in the University of New Mexico’s department of pathology. “The infections tend to be bacterial and can occur about anywhere in the body.”

The illness, called agranulocytosis, can result in a variety of symptoms ranging from fever to a flesh-eating skin condition, Czuchlewski said. Because diagnosis is tricky, illness caused by levamisole poisoning is likely under-recognized.

“The clues need to be put together by the physician,” he said. A doctor needs to ask whether a patient uses cocaine and get an honest answer. “If either of those things don’t happen, then these cases can be missed.”

In 2008, Czuchlewski and others reported a cluster of 11 unexplained cases of agranulocytosis, including one fatality, among New Mexico cocaine users. The research suggested that levamisole caused the illnesses.

By 2010, researchers had identified 19 cases among New Mexico cocaine users, two of whom died, said Dr. Joan Baumbach, a Department of Health epidemiologist.

In the years since, law enforcement seizures of levamisole-tainted cocaine have spiked. The substance was found in 77 percent of cocaine seized in the United States, the U.S. Drug Enforcement Agency reported in 2010. It has also been found in some heroin seizures, the agency said.

New research shows that levamisole is readily metabolized by cocaine users. Researchers in Denver this year reported that, of 249 urine samples from cocaine users, 78 percent contained both cocaine and levamisole. “The study demonstrates that levamisole used to adulterate cocaine was systemically absorbed by cocaine users,” the authors wrote in the study published in April in the Journal of the American Medical Association.

Though researchers are unsure why suppliers add it to cocaine, “levamisol is a widely available, cheap white powder thought to increase the euphoric and stimulatory effects of cocaine,” the authors wrote.

Health officials have few tools for determining the extent of illnesses caused by levamisol, Baumbach said. Physicians aren’t required to report cases of agranulocytosis, she said.

“The exact scope of it I don’t think is well known,” she said.