Rat poison, or rodenticide, is a highly toxic substance designed to kill small mammals. Ingestion by a human is a serious and potentially life-threatening medical emergency. The severity of the outcome depends on the specific chemical agent and the quantity consumed. Because these products are palatable to rodents, accidental ingestion, particularly by children, is a significant public health concern. Immediate professional medical intervention is required following any suspected exposure to prevent severe systemic damage or death.
Common Rodenticide Types and Mechanisms
Rodenticides are grouped into two major categories based on their chemical composition: anticoagulants and non-anticoagulants. Anticoagulant rodenticides, often called “superwarfarins” (e.g., brodifacoum), are the most common type found in household products. These compounds interfere with the body’s ability to recycle Vitamin K, which is necessary for the liver to produce key blood-clotting factors. Blocking this process causes the coagulation cascade to fail, leading to uncontrolled internal and external bleeding.
Non-anticoagulant rodenticides utilize different mechanisms to cause harm. Bromethalin is a neurotoxin that depletes the energy molecule adenosine triphosphate (ATP) in the brain, disrupting nerve function. This leads to swelling of the brain tissue, known as cerebral edema. Another common non-anticoagulant is cholecalciferol, which is a massive overdose of Vitamin D3. Excessive cholecalciferol causes the body to absorb too much calcium, resulting in abnormally high levels of calcium in the blood (hypercalcemia).
Recognizing the Signs of Toxicity
The physical manifestations of poisoning vary significantly depending on the type of rodenticide consumed. For anticoagulant rodenticides, signs of toxicity can be delayed, sometimes appearing hours to days after ingestion, as the body’s existing supply of clotting factors is used up. Symptoms relate to the failure of the blood to clot and include signs of internal bleeding.
This internal bleeding presents as unusual or excessive bruising, frequent nosebleeds, or bleeding from the gums. Internal hemorrhage may also cause blood to appear in the urine (hematuria) or stools (melena). Severe blood loss can lead to generalized weakness, paleness, or excessive fatigue due to anemia. In the most serious cases, bleeding into the brain (intracranial hemorrhage) can cause neurological changes, such as confusion or altered mental status.
Toxicity from non-anticoagulant rodenticides like bromethalin is characterized by neurological symptoms. Because this poison causes cerebral edema, signs may include tremors, seizures, difficulty walking, and agitation. In severe exposures, patients may experience coma, respiratory depression, and increased pressure inside the skull.
Cholecalciferol poisoning, resulting from hypercalcemia, often begins with non-specific signs like vomiting, decreased appetite, and lethargy. As calcium levels rise, patients may experience excessive thirst and urination due to kidney involvement. Uncontrolled hypercalcemia causes calcium to deposit in soft tissues, which can lead to kidney failure, heart rhythm abnormalities, and lung damage.
Immediate Action and Medical Treatment
Ingestion of any amount of rat poison requires immediate, professional attention, regardless of the presence of symptoms. The first step is to call the national Poison Help hotline or emergency services immediately for expert guidance. It is helpful to have the product packaging or the chemical name of the ingested poison available, as this information dictates the specific treatment protocol. Do not attempt to induce vomiting or give the person anything to eat or drink unless explicitly instructed by a medical professional.
Upon arrival at a medical facility, treatment begins with stabilizing the patient, especially if consciousness or breathing is compromised. Diagnostic procedures include blood tests to measure clotting factors, such as the International Normalized Ratio (INR), for anticoagulant exposure. Blood chemistry panels are also used to check calcium and other electrolyte levels if non-anticoagulant exposure is suspected.
For anticoagulant poisoning, the specific antidote is Vitamin K, which restores the liver’s ability to create clotting factors. Depending on the specific rodenticide, high-dose Vitamin K therapy may be required for weeks or months due to the long-lasting nature of some compounds. In cases of severe bleeding, transfusions of blood products containing clotting factors may be necessary.
There is no specific antidote for non-anticoagulant poisons like bromethalin or cholecalciferol; therefore, treatment is primarily supportive and symptomatic. Bromethalin toxicity may be managed with activated charcoal if ingestion was recent, and medications like benzodiazepines are used to control seizures and manage intracranial pressure. Cholecalciferol poisoning requires aggressive management of hypercalcemia, often involving intravenous fluids and medications to reduce blood calcium levels and protect the kidneys.