By Dr. Becker
Arsenic is a heavy metal mineral. Inorganic arsenic is often found in products like herbicides, insecticides, wood preservatives, and some types of insulation. Organic arsenic is used in certain drugs to treat or prevent blood parasites, including heartworm.
How Pets Become Poisoned by Arsenic
In most cases of arsenic poisoning, a pet inadvertently ingests a product containing arsenic that is lying around. However, sometimes toxicity occurs over a long period of time, such as when a dog or cat eats grass that is regularly treated with herbicides containing arsenic.
Arsenic that dissolves in water is quickly absorbed after your pet swallows it. Most of the arsenic that is ingested binds to red blood cells and is distributed to body tissues, with the highest levels accumulating in the liver, kidneys, heart, and lungs. In cases of long-term exposure, arsenic accumulates in the skin, nails, sweat glands, and fur.
It's typically the GI tract, liver, kidneys, lungs, blood vessels, and skin that are most vulnerable to arsenic damage.
Symptoms of Arsenic Poisoning
Symptoms of arsenic poisoning in a pet usually come on suddenly, within a few hours of ingestion, and are quite severe. In some cases, it can take up to 24 hours for symptoms to develop.
Because the GI and cardiovascular systems are affected, blood loss and shock may occur. There is often watery diarrhea that may be tinged with blood, severe colic, dehydration, weakness, staggering, depression, a weak pulse, and loss of consciousness. Circulatory collapse is also possible.
Symptoms can continue for hours or even weeks, depending on the amount of arsenic ingested. In very severe cases, death can be almost immediate.
Diagnosing Arsenic Poisoning
Since your veterinarian or the emergency animal clinic will need to know what your pet has ingested, if you suspect your dog or cat is suffering from arsenic toxicity, it's important to try and bring the suspect product with you.
Unfortunately, most people don't see their pet ingest arsenic. But if your dog or cat is experiencing vomiting or diarrhea, bringing a sample with you to the veterinary clinic can help speed up the diagnostic process.
The vet will need to know when your pet's symptoms started and incidents that could have resulted in a poisoning. There again, if you have products containing arsenic in your house, bring them with you to the vet's office.
A complete blood count (CBC), a chemical blood profile, and a urinalysis will be performed, and a sample of your pet's stomach contents may also be collected. Arsenic found in the bloodstream or stomach contents confirms the diagnosis of arsenic toxicity.
If the poisoning is chronic (long-term), the level of arsenic in your pet's body can be determined by a hair sample.
The goal of treatment in cases of arsenic toxicity is to flush the substance out of your pet's body. If the arsenic was recently ingested, vomiting should be induced to expel as much of the poison as possible. If you actually see your pet consuming the poison, it's important to quickly induce vomiting. I recommend you call your vet or your local emergency clinic for instructions on how to do this safely.
Inducing vomiting can be dangerous under certain circumstances, so don't do it unless you're absolutely sure your pet has swallowed arsenic or another toxic substance. If your pet has already vomited, don't try to induce vomiting or to encourage more of it. Remember that vomiting should never be induced in a dog or cat that is unconscious, having problems breathing, or is showing signs of serious distress or shock.
If you don't know when your pet swallowed the poison, he needs to be seen by a veterinarian right away. Your vet or the emergency clinic staff will perform a gastric lavage (irrigation of the stomach) to flush out the stomach contents, followed by doses of activated charcoal and a medication that will help the bowels to empty. Your pet will probably also be given medicines to prevent damage to the GI tract.
Certain compounds are known to chelate (bind) heavy metals like arsenic, so your pet will probably be given those as well. Many animals suffering from arsenic poisoning need to be hospitalized for a few days until their condition stabilizes. Intravenous (IV) fluids, blood transfusions, and dimercaprol (an antidote to arsenic) will be given as needed while your pet is in the hospital.
Since arsenic severely damages the liver and kidneys, kidney and liver function will be monitored during treatment. Pets with kidney failure will continue on fluid therapy.
Arsenic poisoning in pets is a medical emergency. Unfortunately, in severe cases, very few patients survive unless treatment is started very early, before symptoms progress.