San Francisco authorities are condemning reports that some residents are misusing Narcan, an overdose-reversal drug, to force homeless people off sidewalks and out of public spaces.

Six homeless people have reported being awakened by strangers administering or threatening to administer Narcan while ordering them to relocate, according to the San Francisco Standard. The drug, designed to save lives by canceling the effects of opioids during overdoses, causes severe withdrawal symptoms when given to someone who isn’t experiencing an overdose.

One resident, Nestor Garcia, told the Standard about his experience at U.N. Plaza this summer, where he was dozing on his bicycle when a stranger inserted Narcan into his nose without his consent. “He knew I was still awake; he had bad intentions for sure,” Mr. Garcia said. “The pain was so bad through my whole body. I started flailing around and puking. It felt like a bad dream.”

The misuse of Narcan has gained attention on social media. A viral Instagram video, viewed more than 4 million times, shows someone threatening to use Narcan on a drug addict nodding off in the Tenderloin district. 

The video has received nearly 200,000 likes, with many commenters praising the tactic. “That almost worked better than the Narcan,” one user wrote. “Bro just solved the opiate crisis,” another wrote. 

One man who is homeless and struggling with addiction, Kenneth Byrd, said the practice is spreading fear throughout the homeless community: “They’re using it like a weapon. People are going around doing it just for kicks.”

Another homeless man, Henry Jones, compared the experience to being shot. “I’ve been shot seven times, and being Narcan’d like that was worse. I wouldn’t wish it on my worst enemy,” he told the paper.

The new tactic is the latest in a series of controversial efforts used by San Francisco residents to address homelessness and drug use. Previous methods have included installing garden planters to block encampments, using sprinklers or loud music, and, in extreme cases, hosing down homeless individuals or using bear spray.