A former advanced practice registered nurse with an office in Groton was arrested Wednesday and charged with billing Medicaid for prescriptions that were never provided to the purported recipients, according to the Office of the Chief State's Attorney.

Arlene Dumais, 77, of Cove Road, Preston, was arrested by inspectors from the Medicaid Fraud Control Unit in the chief state's attorney's office and charged with one count each of health insurance fraud and making a false prescription.

According to the arrest warrant affidavit, over a four-year period beginning in 2010, Dumais wrote more prescriptions than any other health care provider in Connecticut for Vivitrol, an injectable medication used to treat opiate and alcohol addiction and for which the state paid $1,100 or more for each prescription.

An investigation by the Drug Control Division in the Department of Consumer Protection found that she wrote nearly 10 times the number of prescriptions as the next highest provider, which was a three-person combined practice. Dumais prescribed Vivitrol on a monthly basis to Medicaid recipients who were either no longer her patients or whom she had never treated, the affidavit states.

Over the four-year period under review, the state Department of Social Services, which administers the Medicaid program, paid nearly $2.3 million for the prescriptions. A random review of three patients revealed at least 21 instances where Medicaid paid for Vivitrol that was not dispensed to the recipient for whom it had been prescribed, the affidavit states.

Medicaid is a federal- and state-funded program that provides health care for low- and no-income individuals.

Dumais was released on a $25,000 nonsurety bond and is scheduled to appear in Hartford Superior Court on May 18.

Health care fraud and making a false prescription are both unclassified felonies, each punishable by up to five years in prison.

The case will be prosecuted by the Medicaid Fraud Control Unit, which was assisted in the investigation by the U.S. Department of Health and Human Services Office of Inspector General, the state Attorney General's Office, state Department of Public Health, state Department of Consumer Protection Drug Control Division and the Town of Groton Police Department.