TOWNSEND — A well-known physician with a long-standing downtown practice has had his state medical license revoked, in part for having a romantic relationship with a patient, according to the state Board of Registration in Medicine.

The decision to revoke Dr. John P. Katzenberg’s medical license was announced recently following a disciplinary decision by the board on Aug. 9.

According to a final report of action, Katzenberg, who practiced internal medicine, “engaged in a romantic relationship with a patient.”

Katzenberg, who has been licensed in the state since 1984, also “prescribed controlled substances to a patient without adequate documentation; failed to maintain adequate medical records as to four patients; failed to respond to a Board subpoena and failed to cooperate in the investigation and adjudication of this matter.”

The report goes on to say that Katzenberg’s practice also has an office in Jupiter, Florida, where his license is still in good standing.

Katzenberg could not be reached for comment. His office at 208 Main St., is closed.

His was the harshest of three disciplinary actions taken against state doctors at last month’s Board of Registration in Medicine hearing: Dr. Daniel C. Marotta, a Springfield based psychiatrist, had his license suspension “stayed as he entered into a probation agreement.” And “the board admonished the license of Dr. David Siegel,” according to the board’s report.

“The Mass BORIM licenses more than 40,000 physicians, osteopaths and acupuncturists. The board investigates complaints and determines sanctions,” according to its page on MassGov.