Brodifacoum

The primary antidote to brodifacoum poisoning is immediate administration of vitamin K₁ (dosage for humans: initially slow intravenous injections of 10–25 mg repeated at 3–6 hours until normalisation of the prothrombin time; then 10 mg orally four times daily as a "maintenance dose"). It is an extremely effective antidote, provided the poisoning is caught before excessive bleeding ensues. As high doses of brodifacoum can affect the body for many months, the antidote must be administered regularly for a long period (several months, in keeping with the substance's half-life) with frequent monitoring of the prothrombin time.[16]

If unabsorbed poison is still in the digestive system, gastric lavage followed by administration of activated charcoal may be required.

Further treatments to be considered include infusion of blood or plasma to counteract hypovolemic shock, and in severe cases, infusion of blood clotting factor concentrate.

Cases of brodifacoum intoxication have been reported in the human medical literature.

In one report, a woman deliberately consumed over 1.5 kg (3 lb) of rat bait, constituting about 75 mg brodifacoum, but made a full recovery after receiving conventional medical treatment.[17]

In another case reported in 2013, a 48-year-old female patient reported 4 days of mild dyspnea, dry cough, bilateral popliteal fossae pain, and diffuse upper abdominal pain. She had no history of liver disease or alcohol or illicit substance abuse. Initial physical examination was remarkable only for mildly pale conjunctivae and mild abdominal tenderness and pain in the left popliteal fossa. A complete blood count and complete metabolic panel were normal. Prothrombin time (PT) was above 100 s, partial thromboplastin time (PTT) was above 200 s and international normalized ratio (INR) was reported as above 12.0. Urinalysis revealed hematuria (blood in the urine). Venous Doppler ultrasound of lower extremities demonstrated left popliteal vein thrombosis. Computed tomography scan of the abdomen demonstrated transmural hematoma, and a fecal occult blood test was positive. A full anticoagulant work-up showed critical reduction of vitamin K-dependent factors II, VII, IX, and X. PT and PTT corrected with mixing studies proving factor deficiency as the cause of the coagulopathy. Lupus anticoagulant studies were negative. Superwarfarin toxicity was suspected and confirmed with an anticoagulant poison panel positive for brodifacoum. The patient was hospitalized and successfully treated with fresh frozen plasma, cryoprecipitate, and vitamin K. In conclusion, paradoxical thrombosis and hemorrhage should raise the suspicion for superwarfarin toxicity in the appropriate clinical setting. Concomitant presentation for thrombosis and hemorrhage with remarkably abnormal PT and PTT should raise the suspicion for brodifacoum poisoning.[18]

In another report, a 17-year-old boy presented to the hospital with a severe bleeding disorder. He was found to have habitually smoked a mixture of brodifacoum and marijuana. Despite treatment with vitamin K, the bleeding disorder persisted for several months. He eventually recovered.[19]

In 2015, 19 inmates in New York City's Rikers Island jail claimed that they had been poisoned with the chemical. The inmates had noticed "what appeared to be blue and green pellets in the meatloaf" they were eating on March 3, and felt ill afterwards. A sample was analyzed and tested positive for brodifacoum; the NYC Department of Correction stated it was investigating the incident.[20][21]

A 20-year-old female college student presented with abdominal pain and blood in urine. She was tested for warfarin, a common anticoagulant also used in some rodenticides, which returned a negative result. Vitamin K and fresh plasma were administered to treat symptoms. Three weeks later, she returned with bleeding into her calf, and was subsequently tested for superwarfarin chemicals. The test showed that brodifacoum was in her bloodstream. She later admitted to consuming seven packets of rodenticide.[22]

A 48-year-old businessman was admitted with a severe nosebleed and abnormal coagulation parameters. Standard treatment of vitamin K and fresh plasma was administered to stem the nosebleed. Two weeks later, he presented again with bleeding into the calf. Continual doses of vitamin K were necessary to counteract the brodifacoum. He denied taking any of the brodifacoum found in his home contained within packages of Contrac.[22]

As of November 26, 2018, at least eight fatalities and 320 cases of severe coagulopathy and bleeding associated with synthetic cannabinoid use had been reported in Illinois, Wisconsin, Maryland, Missouri, Florida, North Carolina, Indiana, Pennsylvania, Kentucky, Virginia, and West Virginia.[23][24][25] The first case occurred in Illinois on March 7, 2018.[26] Brodifacoum was suspected to be present in these products in Illinois. Products named Matrix and Blue Giant from a convenience store in Chicago have tested positive for brodifacoum and AMB-FUBINACA (FUB-AMB).[27][28][29]