Thousands of human lives have been saved at Vancouver's overdose prevention sites and now workers can claim another victory: the life of a pet mouse named Snuggles.

Melissa Patton was working at the Maple Overdose Prevention Site on East Hastings Street Sunday night when a woman brought in the tiny, unresponsive rodent.

"[She] said it had eaten some heroin off the table and had OD'd," said Patton. "It had pretty much passed out and wasn't really breathing. We weren't sure what to do, so I gave it some Narcan orally. Because it was so tiny, I didn't want to puncture anything by giving it an injection."

Snuggles responded to treatment and is now back to normal, according to Maple Overdose Prevention Site worker Melissa Patton. Patton has now adopted the mouse. (Melissa Patton)

"I just put drops on its nose. I know with animals, if you put it on their nose, they brush it off with their paws and lick their paws to clean themselves, so we did that a few times."

Narcan, also known as naloxone, reverses the effects of opioid drugs.

Patton, who is a year away from earning a degree in pharmaceutical sciences, also gave the mouse oxygen and continued to monitor it through the night.

"With babies ... when they're struggling ... skin-to-skin contact is really important, so I had it up on my neck for most of the night and for most of my shift and then I brought it home."

Patton used a syringe to feed Snuggles diluted protein powder. It was only in the morning she knew the mouse would live.

Somebody brought in a mouse who ate heroin and had an overdose, our vounteer's saved the mouse and the mouse has a new home <a href="https://twitter.com/hashtag/vanpoli?src=hash">#vanpoli</a> —@sarahblyth

"Last night, she was really out of it and lethargic," said Patton. "This morning, she had really perked up."

Patton has now adopted Snuggles while its owner gets help.

"She told me she was going into detox today and asked if I'd be willing to take it on. How could I not?"

According to Patton, safe injection site workers do encounter pets that have accidentally overdosed from time to time.

"[When] drugs and paraphernalia are about, there's a risk of children and pets getting into them. A lot of people don't think about that. The idea is that you can use Narcan in so many different situations.

"The fact that this user thought to bring [the mouse] to the safe injection site — that's what we're in the business of."