Several weeks ago, I treated a Beagle with mysterious symptoms. He had a history of lethargy, weakness, trembling, and poor appetite. He was having trouble walking. The dog was 14 , and he lived in a household where a family member had dementia. The owners reported that the family member had a proclivity for feeding the dog from the dinner table.

When I evaluated the dog, I found him to be weak, and I noted that he had poor coordination. He was severely dehydrated and moderately disoriented. He was hyper-responsive to auditory, visual, and tactile stimuli. He appeared mildly jaundiced, and he had a heart murmur. His abdomen was tender when I palpated it. He was in bad shape.

Usually after I evaluate a dog, I have a decent suspicion of the most likely cause for the symptoms. This case, however, was wide open. Elderly dogs are prone to organic disease processes such as liver and kidney failure, diabetes, and cancer. I wondered whether the dog might have liver cancer (which would explain the jaundice) that had spread to the brain (which would explain the disorientation and hyper-responsiveness).

Given the dog’s home circumstances, a condition called pancreatitis also was on the list. Pancreatitis is a condition in which, as the name implies, the pancreas becomes inflamed. Dietary indiscretion is a common cause of pancreatitis, and feeding from the table is a risk factor.

Finally, I was concerned about the potential for toxin exposure. In general, elderly dogs are more likely to become sick from organic diseases than from toxins. However, the home life of this dog put him at risk. Might he have consumed medication dropped on the floor by the person with dementia?

I owed it to the owners to be honest: The prognosis was very guarded. I recommended a battery of tests and treatments, but I was clear that, no matter what happened, the outcome might not be that which was desired. The owners elected to move forward.

Blood was drawn for diagnostic testing, and an intravenous catheter was placed to administer fluids and medications. It was necessary to be judicious with the fluids, since dogs with uncertain cardiac capacity (such as those with heart murmurs) may have trouble tolerating intravenous fluids.

Radiographs of the abdomen showed an irregularity. There was metallic material in the stomach.

The material was sharp and shaped like a crescent. It looked, perhaps, like some sort of earring. But I had a bigger concern: Might the object in question be a penny?

An ultrasound device was used to guide a needle into the bladder to draw a urine sample. This procedure, called cystocentesis, sounds gory but is the gold standard method for urine collection in dogs. The urine was a nasty, turgid brown color. My heart sank. The object in the stomach was probably a penny.

It turns out that pennies are just about the most dangerous items that dogs can consume.

In the olden days, pennies were made out of copper. But copper is expensive, and pennies are only worth one cent. Since 1982, pennies have had only a thin coating of copper. The internal portion of a penny is made of zinc.

Zinc is extremely toxic to dogs. The acidic environment of a dog’s stomach is ideal for corroding pennies. The zinc is subsequently released and absorbed. It causes a condition called hemolysis, in which red blood cells burst. When the blood cells burst, a product called hemoglobin is released into the bloodstream. It shows up in the urine, causing a characteristic brown tinge.

I was especially worried in this case because the metallic object in the stomach was shaped like a crescent. This implied that, if it was a penny, it had been largely dissolved. That meant there was likely to be a high level of zinc in the dog’s system.

Blood tests confirmed that the dog was anemic. I called the owners with the bad news. If the dog was to have any chance of survival, the foreign body needed to be removed. Endoscopy — a procedure using an instrument with a camera and tools to retrieve the foreign object — was the best option, but the prognosis was not good. The owners elected to move forward.

A specialist was called in to perform endoscopy. She removed the foreign object without difficulty. It was a penny.

By this time, the dog’s anemia was becoming critical, so he got a blood transfusion. There was one additional therapy that could be considered: chelation. Chelation therapy involves the use of products that bind zinc in the body and render it inactive.

Unfortunately, the dog’s condition was rapidly deteriorating. He was suffering, and the prognosis was poor even with chelation. The owners elected to put him to sleep.

Most people have no idea that the change in their pocket has the potential to kill their dog. They do not realize that pennies are among the most potentially deadly items on earth.

I propose a simple way to prevent to the problem of zinc toxicosis secondary to penny ingestion. Let’s get rid of pennies and make the nickel the smallest denomination of currency. It will reduce pocket clutter and save dogs’ lives.

Read more by Dr. Eric Barchas:

• Why Do Some Dogs Keep “Showing Their Lipsticks”?
• Let’s Talk About Dogs and Euthanasia: When Is It Time? Should You Be Present?
• What to Do Before You Get to the Vet in 12 Emergency Dog Situations
• 12 Dog Emergencies That Need Immediate Veterinary Attention
• Just How Dangerous Is It to Falsely Call a Pet a Service Dog?

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