A person who died in August in Colorado Springs is the first known instance in El Paso County of a case involving carfentanil without fentanyl, according to a news release by the county’s coroner.

Carfentanil is a powerful synthetic opioid used to sedate large animals like elephants. The drug is 100 times more potent than fentanyl and 10,000 times more potent than morphine, according to the release.

Its ability to produce a false negative on fentanyl test strips is sparking a “new trend” in its usage. The release stated an overdose can be reversed with a “much higher dose” of Narcan compared to opioids such as fentanyl or heroin.

Overdose symptoms for carfentanil, which may go undetected, include slowed or stopped breathing, snoring or gurgling sounds, pinpoint pupils, cold or clammy skin, drowsiness, disorientation, sedation and unresponsiveness.

The El Paso County Department of Public Health provides free Narcan kits during business days at three locations, which can be found on their website.