Veterinarian Tara Montgomery examines a cat named Digit in her clinic in Mississauga in Ontario, Canada. (J.P. Moczulski/Reuters)

It was the third time Heather Pereira had taken her golden retriever to the same neighborhood animal clinic in Kentucky.

The first was on a Friday in October 2014, when Pereira took the injured 4-year-old dog to the Elizabethtown Animal Hospital, not far from Louisville. After the veterinarian sewed up a cut, Pereira requested Tramadol, a drug used to treat pain in both animals and humans. She said the pup had been prescribed the medication in the past and had responded well to it, according to an arrest warrant affidavit.

So the vet gave it to her.

Three days later, she returned — saying her child had flushed the pills down the toilet.

So the vet gave her more.

But it was this third time, on Dec. 4, 2014, that the veterinarian became suspicions. The dog's old cut had not yet completely healed and the animal was back with another. Again, Pereira asked for Tramadol for the dog.

“That’s when I took notice,” Chad Bailey, the veterinarian, told The Washington Post in an interview last week. “The cut looked sharp and clean — not like the kind in nature when a dog is cut on a fence or in a fight.”

Police said Pereira had been intentionally wounding her dog and “vet shopping,” visiting vet after vet to obtain prescription medication for her pet, then taking it. Although these cases appear uncommon, authorities say they underscore the nation's widespread opioid epidemic, showing the lengths people go to obtain drugs for personal use or for sale on the street. They also say it's a concern — one they want to get ahead of.

At the same time, some veterinarians say it's a relatively small problem — arguing that publicizing it will only give drug addicts the idea to do it, and that formally regulating it will only put more of a burden on the vets.

“It’s happening and we are aware of it,” said Jim Arnold, chief of policy and liaison for the diversion control division at the Drug Enforcement Administration. “The whole opioid problem in the U.S. has significantly gotten worse, so when you have this kind of situation in the U.S., where people are seeking these kinds of drugs because of the overwhelming addiction problem ... they will find all kinds of ways to obtain these controlled substances.”

Opioids are the main drivers of overdose deaths in the United States, accounting for more than 33,000 deaths in 2015, according to data from Centers for Disease Control and Prevention.

“The opioid drug problem is big, and it’s not getting any smaller,” Arnold, with the DEA, told The Post.

It is not known how widespread the problem really is because there is no conclusive data tracking cases of vet shopping. But Arnold said drugs such as Ketamine, Tramadol and Valium, which are sometimes prescribed to pets, are used by drug addicts either by themselves or in conjunction with other opioids to enhance the effects.

“It's just another thing,” he said. “When you have this kind of addiction, and it has this kind of control over you, people will do just about anything to obtain these drugs, and they usually do.”

Police said Pereira, who was 23 in 2014, had first taken her dog to another veterinary clinic for a cut and a Tramadol fix.

The third time she showed up to Elizabethtown Animal Hospital, Bailey, the veterinarian, said he thought it was strange.

Bailey said he was also concerned that Pereira kept requesting Tramadol, saying that although it is common for owners to ask how to manage their pets' pain, it is not common for them to know the drug names.

“I just said, 'Wait here and I'll take your dog back,' " he said.

Then he walked out of the exam room and called the police.

Pereira ultimately admitted to authorities that she had cut her dog with her husband's Micro Touch disposable razor blade three different times to obtain Tramadol, according to court documents.

Authorities said she did not have a child, although she had blamed one for flushing the dog's pills, according to the documents.

In 2015, Pereira was convicted on three counts of torture of a cat or a dog, as well as five counts of obtaining a controlled substance by making false statements, which is a felony, according to the News-Enterprise. She was sentenced to four years in prison; however, she was released last month to mandatory reentry supervision after serving two years, according to the Kentucky Department of Corrections.

Prison officials said Pereira moved out of state but would not disclose her location; she could not be found for comment.

Veterinarians no doubt have a hard job as they are reliant on physical examinations, diagnostic testing and pet owners' accounts of  illnesses — and, those in the industry say, people have no doubt taken advantage.

In one case mentioned in a 2002 article in the Pharmacy Times, a dog owner reportedly trained his pooch to cough on command while being examined by the vet, so he could get hydrocodone cough medicine.

Massachusetts's Middlesex District Attorney Marian T. Ryan wrote a letter this month in the Massachusetts Veterinary Medical Association, saying her office is working on a public education campaign to curb it.

“Not long ago, I met a pet owner who said she could not understand why her pet seemed to still be in pain, despite having been prescribed medication,” she wrote. “When she realized that a member of her family had been using the pet’s medication, it suddenly became clear why the pet had not been getting better.

“The misuse of pet medication has serious safety implications — for people and for animals. It is hard to find someone whose life hasn’t been affected in some way by the ongoing opioid crisis in our country. We confront this crisis on many fronts and one of our greatest weapons in this fight is information. Educating people about the signs of drug misuse, available treatment resources and how to properly store and dispose of all medications is a crucial part of helping to stem the tide of overdoses and deaths.”

Many states have electronic databases known as Prescription Drug Monitoring Programs in which physicians can track controlled prescription drugs that are prescribed to patients. But most do not require veterinarians to report the prescribing and dispensing of these drugs.

And some veterinarians argue that forcing them to do so would put an unnecessary burden on them and keep them from focusing on their jobs — caring for the animals.

John de Jong, former chairman of the board of directors of the American Veterinary Medical Association, said that although veterinarians “want to be part of the solution,” some of them are concerned about overregulation.

“Some veterinarians are going to shy away from prescribing medications because reporting them is costly and time-consuming,” he said, arguing that some animals may no longer receive the quality care they deserve.

De Jong, co-owner of and veterinarian at Newton Animal Hospital in Newton, Mass., said that he has not seen any instances of “vet shopping” at his clinic.

“Unless it gets to be a bigger problem, it’s asking a lot,” he said about reporting the prescription medications. “It seems to be making it more of a problem than it is.”

This story has been updated.

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