Facebook feeds have been inundated with misleading ads containing false information about HIV prevention and LGBT advocates, are saying that the tone-deaf tech giant’s refusal to remove the content is creating a public-health crisis.

The paid ads have been viewed millions of times in recent months, They’ve scared patients, potentially those who may be most at risk of contracting HIV, out of taking preventative drugs, known as PrEP, even though health officials and federal regulators have said they are safe.

The ads many of which have been purchased by personal-injury lawyers allege in lawsuits that HIV medications, such as Truvada, actually threaten patients with serious side effects. LGBT groups that work with Facebook say the ads are “false” and have urged Facebook for months to take them down— and Facebook refuses stating that the ads do not violate its policies.

“We value our work with LGBT groups and constantly seek their input,” said Facebook spokeswoman Devon Kearns said in a statement. “While these ads do not violate our ad policies nor have they been rated false by third-party fact-checkers, we’re always examining ways to improve and help these key groups better understand how we apply our policies.”

Demetre Daskalakis, the deputy commissioner for the Division of Disease Control at the New York City Department of Health and Mental Hygiene said the ads, which he has seen on his own Facebook feed, threaten to undo years of work to promote a drug that can cut down on the transmission of HIV and potentially save lives.

“I still see patients,” Daskalakis said. “Four of my seven PrEP patients came in and said, ‘How could you be putting me on this medication that’s so unsafe? My Instagram ads say so.’”

Despite the fact that health officials and federal regulators have said that the HIV prevention drugs are safe personal-injury lawyers claiming to represent thousands of HIV patients say the data actually are on their side — and that they have a role in informing patients about the risks in medication.

“These Facebook ads provide a service to let them know there are options available for them now,” said Robert Jenner, the co-lead counsel in the consolidated lawsuit.