PORTLAND, Maine — A former Portland podiatrist was sentenced Friday to eight years in prison for conspiracy, drug and fraud crimes during a hearing before Judge George Singal in U.S. District Court in Portland.

Dr. John B. Perry, 52, of Cumberland was charged with conspiracy, unlawful distribution of oxycodone and health care fraud, U.S. Attorney Thomas E. Delahanty II said Friday.

Perry pleaded guilty to the charges last December.

Perry wrote prescriptions with no medical purpose, traded prescriptions for cash and cocaine and fabricated patient charts to cover his improper prescriptions, according to court documents.

Court records show that Perry was responsible for the unlawful distribution of more than 18,000 oxycodone pills in 2009 and 2010. His conviction was the third in connection with the drug operation.

A Connecticut man who traded cocaine for prescriptions for oxycodone with Perry was sentenced to a year and three months in federal prison in June of last year.

Dariem Vanalstyne, 25, of New London, Conn., had pleaded guilty earlier that year to four counts of acquiring drugs by deception.

Vanalstyne traded cocaine for prescriptions for oxycodone from Perry on at least four occasions in 2009, according to the prosecution version of events to which Vanalstyne pleaded guilty.

The physician was indicted in February by a federal grand jury on 43 counts of distribution of a controlled substance, one count of conspiracy to distribute oxycodone and one count of health care fraud, according to court documents.

A Windham man also received prison time for getting prescriptions for oxycodone illegally from Perry.

Manford Rideout, 43, was sentenced in March of last year in federal court in Portland to a year and a day in prison for conspiracy to acquire drugs by deception. Court documents state that Rideout obtained more than 20 prescriptions for oxycodone, a powerfully addictive painkiller, from Perry between March 4, 2010, and Sept. 20, 2010.

In exchange for introducing other people to Perry, Rideout would receive a “cut” of any prescriptions the doctor wrote, according to the prosecution version of events to which Rideout pleaded guilty. Rideout also told investigators he gave the doctor cash payments as a “tip” for giving him so many prescriptions, which were written outside of the doctor’s medical office. One of them was written at a Portland bar, according to court documents.

The convictions were the result of an investigation by the U.S. Drug Enforcement Administration, the U.S. Department of Health and Human Services’ Office of Inspector General, the Federal Bureau of Investigation, the Maine Drug Enforcement Agency and the state Attorney General’s Healthcare Crimes Unit.