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FDA Statement

Statement from FDA warning about significant health risks of contaminated illegal synthetic cannabinoid products that are being encountered by FDA

For Immediate Release:
Statement From:
Scott Gottlieb, M.D.


The U.S. Food and Drug Administration has become aware of reports of severe illnesses and deaths resulting from the use of synthetic cannabinoid (marijuana) products that have been contaminated with brodifacoum, a very long-acting anticoagulant commonly used in rat poison. These unapproved products are being sold in convenience stores and gas stations as substitutes for marijuana under names such as “K2” and “Spice.” Use of these illegal products pose significant public health concerns for both individuals who may use the contaminated products and the U.S. blood supply, as there is the potential for contamination of blood products donated by those individuals who have used these substances.

There are a number of synthetic marijuana products being illegally marketed and used for their psychoactive effects. The FDA has previously worked with the Drug Enforcement Administration (DEA) to place several synthetic cannabinoids into Schedule I of the Controlled Substances Act to avoid an imminent hazard to public safety. Generally, these products have been known to be associated with adverse effects including rapid heart rate, vomiting, violent behavior and suicidal thoughts, and an increase in blood pressure, as well as causing reduced blood supply to the heart, kidney damage, and seizures.

But despite our efforts, certain entities continue to bypass state and federal drug laws by making and distributing these products – often marked or labeled as “not for human consumption” – and changing the structure of the synthetic chemicals to try to skirt legal requirements. And in some cases, some of the producers of these synthetic cannabinoids have added brodifacoum, which we have heard is because it is thought to extend the duration of the drug euphoria or “high.”

But the presence of brodifacoum in these illegal and unregulated products poses severe health risks because it can cause severe bleeding. In recent months, hundreds of individuals in about 10 states – many in the Midwest – have been hospitalized after experiencing such complications. Unfortunately, there also have been several related deaths. Our colleagues at the U.S. Centers for Disease Control and Prevention (CDC) have been working with state health departments on this matter. The presence of brodifacoum in these illegal compounds poses a significant public health hazard.

Today, we’re joining together to send a strong warning to anyone who may use synthetic marijuana products that these products can be especially dangerous as a result of the seemingly deliberate use of brodifacoum in these illegal products.

Individuals who have possibly used synthetic marijuana products should be vigilant for signs of bleeding. These include easy bruising, oozing gums, and nose bleeds. People experiencing these symptoms after using synthetic marijuana products should immediately seek medical attention, as the effects of brodifacoum are treatable.

People with certain pre-existing conditions or those already taking certain prescription and over-the-counter drugs may be at a higher risk for such bleeding and should seek prompt medical treatment.
We also want to alert health care providers, particularly those delivering care in emergency settings, to be aware of these risks and consider the possibility of synthetic cannabinoid exposure when individuals present with unexplained bleeding. Standard coagulation tests, such as the prothrombin time, can be dramatically elevated in these settings, and prompt treatment with high doses of vitamin K and other supportive care can potentially be life-saving.

As discussed, we’re also concerned about the potential contamination of donated blood products. The FDA has received several reports of donors who used synthetic cannabinoids contaminated with brodifacoum. Because of its long half-life, the bleeding risk from brodifacoum, which prevents vitamin K from being reused within the body, can persist for weeks. Consequently, potential safety concerns exist for both the blood donor and the donated blood components, given the potential impact on coagulation because of its long-acting vitamin K antagonist activity. For that reason, the FDA recently shared information with blood establishments about this risk.

Given the known and unknown risks associated with these synthetic cannabinoid products, the FDA urges individuals to avoid using them, especially since there’s no way of telling which synthetic marijuana products have been contaminated with the powerful anticoagulant brodifacoum. We’ll continue to monitor this issue and take additional steps as appropriate along with our federal partners at the CDC and DEA, state and local health departments, and blood establishments.

The FDA, an agency within the U.S. Department of Health and Human Services, protects the public health by assuring the safety, effectiveness, and security of human and veterinary drugs, vaccines and other biological products for human use, and medical devices. The agency also is responsible for the safety and security of our nation’s food supply, cosmetics, dietary supplements, products that give off electronic radiation, and for regulating tobacco products.

Statement from Commissioner Scott Gottlieb, M.D.; Peter Marks, M.D., Ph.D., director, Center for Biologics Evaluation and Research; and Janet Woodcock, M.D., director, Center for Drug Evaluation and Research



Megan McSeveney

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