Police arrested Donna Monticone, 49, in November 2020 after investigators discovered she had removed the high-powered synthetic opioid from glass vials meant for surgery patients at Yale Reproductive Endocrinology and Infertility, the DEA said.
She injected herself with the drug and replaced what she used with saline so the vials would appear full, officials said.
The Justice Department found that 75 percent of the fentanyl doctors at the Orange medical center prescribed to patients from June to October 2020 was diluted with saline.
Monticone pleaded guilty to tampering with a consumer product in March 2021, the DEA said.
A civil audit of Yale Medicine that followed Monticone's arrest found 685 instances of sloppy bookkeeping that violated the Controlled Substances Act.
"The investigation also found that Yale failed to maintain an initial inventory, failed to keep a record of the destruction of controlled substances, and was unable to readily produce DEA e222 forms, which are required records for purchase and sale of Schedule II controlled substances," the DEA said.
Auditors also said they found discrepancies with 665 units of controlled substances, including fentanyl, ketamine, and anesthetics.
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