Most cocaine diluted with unsafe livestock drug

Tuesday, December 29, 2009

Most cocaine coming into the United States has been diluted with a veterinary drug that is used to deworm horses and other animals but can cause severe illness and death in humans, public health experts say.

So far, eight cases of illness caused by the drug levamisole have been identified in San Francisco, one of a handful of cities in the country where pockets of sickness caused by the drug have been found.

All of the cases in San Francisco involved women who used either crack or powder cocaine. At San Francisco General Hospital, where the first cases of the illness were diagnosed, 90 percent of 200 patients who recently tested positive for cocaine also tested positive for levamisole. Most of them did not become ill.

Levamisole can significantly reduce the number of white blood cells in the body, a condition called agranulocytosis. Symptoms include fever, swollen glands, painful sores in the mouth and anus, and an infection that won't go away. In San Francisco, patients with levamisole poisoning also are getting serious skin conditions that make their skin look black.

Doctors and lab specialists at S.F. General are leading state and national efforts to diagnose and treat patients.

"The big question we have right now is, if 90 percent of cocaine users in San Francisco are positive for levamisole and are being exposed to this compound, then why aren't 90 percent of them in the emergency room with these side effects?" said Kara Lynch, associate chief of the chemistry and toxicology lab at S.F. General.

Cocaine often is diluted with other drugs or chemicals both to increase its weight - dealers can stretch out the amount of powder they sell - and to add to or reduce its potency. Public health experts don't know exactly why levamisole has been added to cocaine, but one theory is that the drug has been shown in animal studies to augment the effects of cocaine.

U.S. public health officials first warned of the risk of illness from levamisole in cocaine in September. The U.S. Centers for Disease Control and Prevention earlier this month released a report noting that 69 percent of cocaine recently seized in the United States had been tainted with levamisole, and illness from exposure to the drug has been found in at least four states.

So far the illness seems to be more common in women than in men, and most of those affected have been in their 40s and smoked the cocaine in crack form. The eight people in San Francisco who were sickened by levamisole survived, but at least one person died in New Mexico, according to the CDC.

"We need people to know that you're not getting pure cocaine anymore. You're exposing yourself to the effects of an anti-parasite drug instead of cocaine," said Dr. H. Westley Clark, director of substance abuse treatment with the U.S. Substance Abuse and Mental Health Services Administration. "You're not getting high off of cocaine, you're getting sick off of levamisole."

Because many of the symptoms of the illness are the same as the flu, Clark said health care providers need to be aware that more testing may be necessary to make sure cocaine users aren't sick with something more serious than influenza.

Dr. Jonathan Graf, an assistant professor in rheumatology at S.F. General who works with the Rosalind Russell Arthritis Research Center at UCSF, said doctors are mystified as to why San Francisco patients are getting the condition that blackens their skin and makes it appear to be "sloughing" off, while patients in other areas are not.

It may be that the illness is still being identified, and as more doctors and public health officials become aware of the problem, more cases - and more symptoms - will be discovered, he said.

"I have a feeling this is out there a lot more than we're giving it credit for," Graf said. "There are probably many cases of this going on around the Bay Area and elsewhere. There are probably a lot of people not coming in to emergency rooms or doctors."

The illness was discovered at S.F. General when dermatologists saw two patients with the serious skin condition. They suspected the skin problems were related to an autoimmune disorder and called in Graf. At the same time, doctors at UCSF had discovered similar symptoms in another couple of patients, and reports were starting to come in from other states about the unusual illness.

When doctors realized that all of those patients at the two hospitals were cocaine users, Lynch offered to test other cocaine-positive patients for levamisole and found in October that about 180 out of 200 of them also had levamisole in their system.

The question then became why the levamisole was affecting some patients, but not others. One theory of Graf's is that the levamisole may be triggering an autoimmune reaction in patients who are already susceptible to autoimmune disorders.

"Maybe these patients are predisposed to getting an autoimmune disease, but there's nothing that set them off before," Graf said. "Maybe the levamisole increases to a certain level and suddenly you start seeing cases."

From: http://www.sfgate.com/cgi-bin/article.cgi?f=/c/a/2009/12/29/MNDS1B6HAS.DTL&tsp=1