Warfarin-type rat poison acute poisoning: intensive resuscitation treatment

2021-07-29 04:42 PM

For most of the rat poison warfarin, the exact amount is difficult to determine, and the clinical setting and the type of drug used to determine toxicity.

Not all warfarin rat drugs cause medical recognition. Evaluation is determined by the clinical circumstances and the toxicity of the exposure. A nontoxic dose is < 1 mg. However, with most rodenticides warfarin, the exact amount is difficult to determine, and the clinical circumstances and type of drug used to determine if exposure is toxic.

Warfarin and related anticoagulant rat poisons inhibit the synthesis of coagulation factors II, VII, IX, X requiring vitamin K in the liver. The anticoagulant effect appears after 2-3 days. Long-acting anticoagulants (brodifacoum, bromadiolone, coumatetralyl, difenacoum) cause coagulation disturbances lasting weeks to months.

The usual oral dose (10-20mg) in one time does not cause serious acute poisoning. In contrast, prolonged use of low-dose warfarin (2 mg/day) may cause coagulation or bleeding disorders. The lowest reported fatal dose for warfarin was 6.667 mg/kg.

Definite diagnosis

Ask patient

Exploiting medical history and evidence: drug name, drug form (ARS Rat Killer, Rat - K, courmarin, dlcourmarln, coumadin... packaged in powder or tablet form), the quantity taken, time, time after taking it to the palpation gland, treat at the palpation gland.

Ask to bring medicine, medicine packaging.


Prominent is the bleeding that manifests after 2-3 days onwards.

In the first 1-2 days, the patient has no clinical symptoms.

Hemorrhage of different degrees: bleeding gums, nosebleeds, bleeding under the eye conjunctiva, brain bleeding, hematoma in the muscle.

Coagulation disorders causing bleeding to appear as early as 8-12 hours but usually after 2-3 days.

Other possible symptoms: lethargy, headache, dyskinesia, abdominal pain, nausea. More severe may experience rhabdomyolysis, respiratory failure, convulsions, coma...


Coagulation tests: reduction of factors II, VII, IX and X reduces PT% and prolongs INR (high risk of bleeding if INR > 5).

Other tests: complete blood count, blood type, and blood cross-section in case of massive bleeding due to coagulopathy for blood transfusion.

Blood biochemistry: increased GOT, GPT, urea, creatinine, CK.

Other tests depend on the patient's condition.

Differential diagnosis

Poisoning with other rat poisons

Zinc phosphide group: multi-organ damage, initial abdominal pain, vomiting, early diarrhea, metabolic acidosis, cardiac arrhythmia, acute pulmonary edema, rhabdomyolysis - renal failure, acute hepatitis, coagulation test normal blood.

The fluoroacetate group: arrhythmia, acute heart failure, causing muscle hypertrophy, convulsions, normal coagulation tests.

Blood disease, liver failure

No history of acute poisoning, other systemic symptoms.

Diagnosis of complications

Bleeding organs: lung, digestive, urinary, abdominal, central nervous...


Stabilize life function

Respiration and circulation. Pay special attention to cases of cerebral hemorrhage with impaired consciousness and hemodynamics.

Measures to prevent absorption

Gastric lavage if necessary and the amount of medication taken is large, come early.

Activated charcoal: 1 g/kg dose with sorbitol can be repeated after 2 hours if the patient takes a large amount, comes early.

Measures to eliminate toxins

There is no effective remedy for this type of poisoning.

Treatment with an antidote (specific antidote)

Vitamin K 1: in the presence of obvious coagulopathy:

Usage: children at least 0.25mg/kg, adults at least 20mg/time, 3-4 times/day. Maintain 10-100mg/day divided into 3-4 times until INR returns to normal. Can be taken orally or injected under the skin.

Monitor: test INR every 12-24 hours.

Do not use vitamin K 1 for prophylactic treatment in the absence of coagulopathy.

Fresh frozen plasma: when there is coagulation disorder PT < 40%, bleeding, fresh frozen plasma transfusion, whole blood transfusion when bleeding causes severe blood loss.


Educate on the safe and rational use and storage of rat poison.