Smoking synthetic marijuana has been linked with acute kidney injury, according to federal health officials. The designer drugs have been associated with hypertension, rapid heart rate, seizures, and hallucinations, but today’s report is the first to link them with kidney problems.
An investigation into 16 cases of unexplained acute kidney trouble began in March 2012, when the initial 3 cases were reported to the Wyoming Department of Health. The department contacted the Centers for Disease Control and Prevention (CDC) and issued a statewide alert to hospitals and clinicians to report similar cases. Collaboration among several state health departments, poison control centers, forensic laboratories, and individual clinicians identified the additional cases.
In addition to Wyoming, cases were reported in Rhode Island, New York, Oregon, Kansas, and Oklahoma. All 16 patients—15 males and 1 female—were treated in emergency departments and then hospitalized. They ranged in age from 15 to 33 years, and all told health officials they had smoked synthetic marijuana shortly before becoming ill.
The patients’ symptoms included nausea, vomiting, and abdominal or back pain. All had elevated creatinine levels, indicating impaired kidney function, and several had biopsies that showed kidney damage. Five needed kidney dialysis and 4 were treated with corticosteroids. No deaths were reported.
Synthetic marijuana, sold under names including Spice, K2, and Mr. Happy, first appeared in the United States in 2009, the CDC reported. They’re made with synthetic cannabinoid compounds, which act on the same cell receptors as tetrahydrocannabinol (THC), the active ingredient in marijuana. The synthetic compounds then are mixed with dried plants and smoked as a substitute for marijuana. Packaging labels often use intentionally misleading language indicating the product is incense or not intended for human consumption.
According to the National Institute on Drug Abuse, the synthetic cannabinoid compounds can bind more tightly with THC receptors than THC itself, leading to a more intense but less predictable high. Five of the 16 patients described in today’s Morbidity and Mortality Weekly Report smoked synthetic marijuana containing a compound called XLR-11, which health officials and toxicologists haven’t seen before in these products.
Even though all 16 patients recovered, the CDC warned that acute kidney injury increases the risk of chronic and end-stage kidney disease. Clinicians who treat young, otherwise healthy patients with acute kidney injury should ask if they’ve used synthetic marijuana and report suspected poisoning cases to a regional poison control center (1-800-222-1222) and their state health department.