A newly unsealed federal search warrant says a Minnesota doctor who treated Prince in the weeks before he died expressed concern that the musician was suffering from opiate withdrawal.

The document unsealed Thursday says Dr. Michael Todd Schulenberg saw Prince on April 7, 2016, at the request of Prince’s friend, Kirk Johnson, and prescribed Vitamin D and ondansetron under Johnson’s name.

The document says Johnson called the doctor on April 14 and asked him to prescribe a pain medication for Prince. Authorities say Schulenberg prescribed oxycodone for Prince, again under Johnson’s name. Schulenberg disputes that, but is paying $30,000 to settle a civil violation.

The doctor also saw Prince on April 20 when Prince was reporting feeling antsy. A urinalysis tested positive for opioids.

Prince was found dead of a fentanyl overdose the next day. The doctor is not facing criminal charges and his attorney says he had no role in Prince’s death.