this would be a good time to tell them to stop:
Cocaine's a hell of a drug, and even more so when laced with another drug that's commonly used to deworm opossums. Federal agents have found that 69 percent of cocaine shipments seized entering the United States contain levamisole, a veterinary drug linked to serious weakening of the immune system in humans. Here's the real funny part: no one knows why.
This comes from a recent report by the Centers for Disease Control and Prevention (CDC) on the immune system condition, known as agranulocytosis. The paper tracks 21 cases from New Mexico and Washington State linked to cocaine, including one death, but cautions that many more cases have probably gone under the radar of public health officials.
Pointed to by Insty