How many Americans are using prescription opioid painkillers? About one in three.

That’s the stunning number in a new survey released Monday from the National Institute on Drug Abuse, which calculated that a whopping 91.8 million Americans used drugs like OxyContin or Vicodin in 2015.

And nearly five percent of the adults surveyed told researchers they took these drugs without their doctor’s permission, the study reported.

They didn’t get their meds from some seedy drug dealer, either.

“The most commonly reported sources were friends and relatives for free,” the study reported. “Or a physician.”