Rat Poison Ingestion: Dangers and Treatments

Rat poisons—also known as rodenticides—are common household agents comprised of multiple active ingredients that are highly toxic to mammals, humans included. Exposure to these chemicals must be kept to a minimum; while some rodenticides may cause mild irritation when touched, ingesting any rodenticide is extremely dangerous and can lead to internal bleeding, organ failure, paralysis, coma, and death.

Signs of toxicity may not show up for several hours or days following exposure. If you suspect that you or your loved one has ingested rat poison, don't wait for signs that something is wrong. Call poison control immediately at 1-800-222-1222. Pets that ingest rat poison are at serious risk as well. The Animal Poison Control Center can be reached at 1-888-426-4435.

Brown Rat Eating Grain in a Barn — Nature Picture Library / Getty Images

What Is Rat Poison?

Anticoagulants (blood thinners) are found in most rat poison products, and are responsible for more than 50% of rodenticide-related calls to the Poison Control Center each year.

The first anticoagulant rat poison, warfarin, hit the market in the 1950s. Rodents quickly became resistant to it, and as a result, "superwarfarin" rat poisons were derived from warfarin, which have more prolonged effects and are at least 100 times more toxic. The two superwarfarins that are responsible for most rodenticide poisonings in humans are bromadiolone and brodifacoum.

Anticoagulant warfarin (brand names Coumadin and Jantoven) is a common medication prescribed to people who are at risk of heart attack or stroke. It is specially formulated to reduce the likelihood of dangerous blood clots, though its use still carries a risk of severe bleeding.

Thallium sulfate is another active ingredient formerly used in rat poison that is colorless and odorless. It was banned in the United States in 1972 due to overwhelming reports of accidental exposure, especially in children.Although exceedingly rare, thallium poisoning still occurs, typically from old rodenticide products. The compound is rapidly absorbed through the skin and gastrointestinal tract and exposure to as little as 8 milligrams (mg) can be fatal.

Among the many brands of rat poison available, you may encounter:

Havoc Rodenticide Bait: an anticoagulant pesticide containing brodifacoum
Tomcat Bait Chunx: a single-dose pesticide (only needs to be ingested once) containing bromethalin
Bell Contrac Rodent Control: an anticoagulant containing bromadiolone
Neogen Rodenticide: an anticoagulant containing diphacinone
ZP Tracking Powder: an indoor rodenticide containing cholecalciferol

Like warfarin, cholecalciferol (vitamin D3) is also used by humans for health purposes. Some people take vitamin D3 supplements to help their body absorb calcium and phosphorus—two minerals that are necessary for building and maintaining strong bones. Not to mention, cholecalciferol is synthesized in the skin when we come in contact with sunlight.It would take a large amount of cholecalciferol to cause calcium toxicity (hypercalcemia) in humans. Thus, cholecalciferol poisoning is far more rare in people than it is in pets.

In 2017, there were over 10,000 reports of rat poisoning in people, most of them due to anticoagulants. Over half of those cases were children ages six and under.

How Rat Poison Works

Most rodenticides on the market are comprised of anticoagulant compounds. These are usually multiple dose poisons that take 4 to 14 days of a rodent feeding on them for death to occur. Once ingested, the poison inhibits blood clots from forming, resulting in excessive internal bleeding.

Whereas some rat poisons are lethal after just one exposure, others require multiple doses to kill. Secondary poisoning is an issue that largely affects wildlife, farm animals, and pets as well. An example of this is when a household cat eats a mouse that has been poisoned with rodenticide.

Here's how they work:

Anticoagulants: cause internal bleeding that may go unnoticed for several days after exposure. Signs of poisoning in pets include trouble breathing, lethargy, seizures, shaking, bloody stool, bleeding from the gums, and abdominal distention.
Bromethalin: a neurotoxin that causes cell death in the central and peripheral nervous systems. A pet that has eaten bromethalin may vomit, seize, lose control of their legs, or fall into a coma, beginning 8 to 12 hours after exposure.
Cholecalciferol: a form of vitamin D that leads to calcium toxicity, kidney damage, and heart failure. Signs of poisoning in pets include loss of appetite, vomiting, frequent urination, and depression, beginning 12 to 36 hours after exposure.
Zinc phosphide: a substance that turns to gas inside the body once consumed, crippling the body's major organs. Signs of toxicity in pets include anxiety, pacing, weakness, and convulsions, beginning 4 to 18 hours after exposure.
Strychnine: a compound that triggers seizures so severe they inhibit breathing. In animals, seizures are the primary symptom, beginning 15 minutes to 2 hours after exposure.

Ingestion is not the only form of exposure. With the exception of warfarin, all rodenticides are highly toxic when ingested or inhaled. Warfarin is also highly toxic when ingested, but there is low toxicity associated with touching or inhaling it. Diphacinone, bromadiolone, brodifacoum, and bromethalin are toxic to touch as they absorb into the skin. Take caution to protect your eyes when working with rodenticides; most can cause mild to moderate eye irritation.

Symptoms of Human Poisoning

Symptoms of rat poisoning don't show up right away. In some cases, there may not be any symptoms at all.If a person doesn't realize they have ingested rat poison, they may confuse their symptoms for another condition. Symptoms to be aware of include:

Anticoagulants: spontaneous bleeding from the gums, nose, or skin. Signs of internal bleeding include lightheadedness, shortness of breath, pain, nausea or vomiting. Symptoms may not be obvious, especially in children.
Bromethalin: upset stomach or altered mental status. Signs of cerebral edema include visual, behavioral, or mental disturbances, headaches, confusion, vomiting, lethargy, or loss of consciousness.
Cholecalciferol: dehydration, extreme thirst, increased urination. Exposure can result in heart and kidney damage if the excess calcium accumulation is not corrected.
Zinc phosphide: vomiting, hyper-excitability, chills, convulsions, shortness of breath and coma. Inhaling zinc phosphide can cause anxiousness and breathing difficulty.
Strychnine: muscle spasms and seizures. Symptoms can set in within 15 minutes and progress until breathing is impaired.

Some rat poison products contain blue or green dye so that you can quickly identify when a child or pet has touched or consumed them.

Treatment

First and foremost: if you or your loved one has ingested rat poison, do not attempt to treat yourself with medication or natural remedies. Before doing anything else, consult with a poison control expert right away.

Labels on rodenticide products include first aid instructions, and it's important to read them before you open the product, just in case you are exposed.

For example, the product label for CONTRAC All-Weather BLOX (an anticoagulant containing bromadiolone) advises:

If ingested, you should first call poison control, then sip a glass of water if you're able to swallow. You should not try to induce vomiting unless otherwise advised by poison control or your doctor.
If your skin or clothing is exposed, you should remove contaminated clothing, rinse skin immediately for 15 to 20 minutes, and call Poison Control for treatment advice.
If your eyes are exposed, you should flush your eyes (while open) with water for 15 to 20 minutes, remove any contact lenses after five minutes, then continue to flush and call Poison Control.

A Poison Control expert may recommend that you go to the hospital. Expect to receive oral and/or intravenous medication.

Anticoagulants inhibit a vitamin K enzyme necessary for blood clotting. The standard treatment to reverse this effect is vitamin K1 therapy administered intravenously by a physician. Superwarfarins are formulated to have long-lasting effects, consequently requiring oral doses of vitamin K1 therapy taken another 168 consecutive days (on average).

Hypercalcemia due to cholecalciferol poisoning is treated with intravenous calcium gluconate. There are no antidotes for treating non-anticoagulatory rodenticides like bromethalin, strychnine, or zinc phosphide. Supportive care is given to patients hospitalized with this type of poisoning, which may include intravenous fluids and medications for specific symptoms. Activated charcoal or ipecac is sometimes used to detoxify the gastrointestinal tract.

Does milk dilute poison?

No, that's a myth. If you have swallowed poison, drinking small amounts of water or milk may help soothe burning or irritation temporarily, but it will not neutralize the toxins in your body.

Prevention

As of 2011, rodenticide bait must be sold in the form of blocks rather than pellets or loose bait and it must be contained inside a tamper-proof bait station.If you have any of the older forms of rat poison around the house, consider disposing of it and purchasing a safer bait.

Before you bring rodenticide into your home, see if there are any other methods of control that you have not tried.

Make sure cracks and crevices are completely sealed, along with garbage cans and leaky faucets. Keep foliage around the perimeter of your home trimmed to reduce the likelihood that mice will nest there. Never leave food or wrappers lying around the house and toss leftover food items into a tightly sealed trashcan outside of your home.

Rodenticide should always be stored in cool, dry places that are completely out of reach of children and pets. Avoid placing rat poison in your kitchen. If possible, opt for rat traps first. Place traps behind appliances or other areas that are inaccessible to children and pets. Keep in mind that house mice rarely venture far from their nests, so you do not need to disperse traps around an entire living space. You can place them within 10 to 12 feet of the nest.

Rat poison should be your last resort. Other effective, non-toxic repellents to consider are:

Fresh Cab Botanical Rodent Repellent: This EPA-registered natural repellent is made of balsam fir oil, fragrance oil, and plant fibers, and safe for both indoor or outdoor use.
Peppermint oil: Rats loathe the smell. Wet cotton balls with essential oil and place them near the nest or wherever you find droppings. This isn't likely to eliminate pests, but it's worth a shot.
Vinegar: Any strong-smelling substance that is non-toxic to you or your pets may keep mice away temporarily. Consider mopping the floor with vinegar on a regular basis.
Diatomaceous earth: This powdery substance is made of fossilized aquatic organisms (diatoms). It is non-toxic to humans but causes a rodent's insides to completely dry out when ingested.

Prevent exposures from happening in the first place. Wear gloves, protective eyewear, and a mask when handling rat poison, dead rodents, or nesting materials. Remember to wash hands with soap and water thoroughly after you're done, along with any surfaces or handles you may have touched in the process.

A Word From Verywell

Mice are known to carry a multitude of dangerous viruses and diseases, posing a serious threat to your health and home. They can be quite tricky to get rid of, leading many people to consider rat poison as a last-ditch option to eliminate them. While undoubtedly effective, rat poisons carry their own risks as well. Read labels carefully, wear protective gear, and only place rodenticide where it cannot be accessed by children or pets. When it comes to handling toxic substances, you can never be too careful.

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