NASHVILLE, Tenn. (WKRN) – There are two trends emerging from the latest suspected overdose death data from the Metro Public Health Department: a slight decrease in overdose deaths this year compared to the same period last year and an animal tranquilizer showing up in more Davidson County overdoses.

According to the Metro Public Health Department, 166 people didn’t survive an overdose in Nashville last quarter, which is a nearly 10% drop in deaths from the same time last year.

Brian Sullivan with the Prevention Alliance of Tennessee said that any loss due to opioids is a strategy, but “there is a glimmer of hope in those overdose deaths going down.”

He believes this decrease can be attributed to a wide range of harm reduction measures, including new state and local programs, more mental health resources and the launch of 988, the distribution of accurate fentanyl information from the health department and more money going to organizations like Prevention Alliance.

“It really takes all of these different things working cohesively to curb overdose deaths in your community,” Sullivan said.

However, while traveling around South Nashville to assist people suffering from addiction Friday night, Miriam Field with Mainline Harm Reduction offered an additional theory for the trend in overdose deaths.

“The tolerance is there,” she said, “So, the fatal overdose rates will go down if tolerance is up.”

What Field is seeing on the nights she is traveling around the area is the impact of the veterinary tranquilizer xylazine in Nashville.

According to MPHD, xylazine has been found in 6% of suspected overdose deaths so far this year compared to 2.6% last year.

“Every day I go out with a full first aid kit and every day I come home with it empty because xyalzine is a drug that causes lesions, corrosion of the skin, especially when it’s being injected,” she said.

Xylazine is not approved for human use and according to the NIH, it is becoming increasingly more common in the United States over the past few years. Researchers also say it is often mixed in with other drugs like fentanyl.

“People report using xylazine-containing fentanyl to lengthen its euphoric effects,” writes the National Institute of Drug Abuse.

Field also notes that, unlike fentanyl, naloxone can’t be used to treat overdoses from xylazine, which poses a new challenge to those trying to prevent overdoses in Middle Tennessee.

“There is always going to be something and we have seen a steady progression in the potency of our drug supply,” Field said,