Some batches of synthetic cannabinoids have been contaminated with brodifacoum, a long-acting vitamin K antagonist (superwarfarin) used as a rodenticide. A person exposed to affected cannabinoid will develop a severe coagulopathy.

Major criteria:

(1) prothrombin time >= 14.8 seconds or INR >= 1.3, consistent with a vitamin K dependent coagulation factor deficiency

(2) exposure to a synthetic cannabinoid within the past 30 days


Minor criteria:

(1) active bleeding

(2) exposure to synthetic cannabinoid obtained from a person with known superwarfarin poisoning

(3) presence of superwarfarin on an anticoagulant poisoning panel


Diagnosis of synthetic cannabinoid-associated coagulopathy: both major and >= 1 minor criteria


If a patient is being treated with an anticoagulant, then the diagnosis requires:

(1) exclusion of overdose with that anticoagulant

(2) identifying a superwarfarin on an anticoagulant poisoning panel

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