A woman who adopted a stray dog quickly learned he came with more than just a cute face.

On May 23, TikTok user @madysonheaton posted a video about the stray dog she found and took off the street. In her eyes, she was "tricked." The dog's adorable eyes and perfectly floppy ears had her melting. And without hesitation she immediately brought him home.

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What the small dog tricked her on was how much it would cost to keep him. She took him to the vet for a quick checkup, but it quickly turned into an expensive visit. She learned the dog has heartworm disease, a potentially deadly parasite transmitted by mosquitoes. The visit, diagnosis and treatment ended up costing her $3,000.

The caption reads: "He's lucky he's cute."

Although it was a shocking price tag for a dog she rescued off the street, it didn't matter. He was her new pet. And like any pet parent, she is dedicated to keeping him safe and healthy.

Newsweek reached out to @madysonheaton via TikTok for additional information.

Heartworm disease, unfortunately, is common in dogs and occurs in all 50 states of the United States. PetMD reports that nearly 1 million pets in the U.S. are heartworm-positive, and that number growing.

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As this dog owner learned, treatment can be complicated and expensive. The cost of treatment depends on the dog's size and the severity of the disease, and it can range between $500 and $6,000.

The TikTok video went viral, amassing over 3 million views, 804,100 likes and 833 comments so far.

"That head turn. That baby knows he's got you wrapped around his finger (or paw)," said one viewer.

One commented: "Dogs just exist to spend all of our money. They're lucky they're so cute."

Someone pointed out: "He will be soooo insanely loyal to you too most likely!! Their love is unmatched. Thank you for saving him!"

Another added: "I did the same thing. worth every penny. my only regret is I didn't find her earlier."

How to Treat Heartworms in Dogs

The American Kennel Club says owners should restrict activity for heartworm-positive dogs, as exertion will increase the rate of damage to their heart and lungs. To kill the worms, vets will prescribe medications, but in extreme cases they might resort to surgery and physically pull the worms out.

Yearly testing and administration of preventive medicine are recommended to keep dogs from getting heartworm. The medication is also effective in fighting against parasites, roundworms, hookworms, fleas and tapeworms.

Do you have funny and adorable videos or pictures of your pet you want to share? Send them to life@newsweek.com with some details about your best friend, and they could appear in our Pet of the Week lineup.