Benjamin Anazodo, 53, tried to cover his tracks by recording that the powerful painkillers - normally given to the terminally ill - were legitimately prescribed to the dead man's wife and daughter, for complaints including period pains, the court was told.
Lee Welch, 44, a drug addict for many years, registered at Anazodo's newly opened surgery in September 1992. He was initially prescribed the heroin substitute methadone but later a regular supply of the Class A opiate drug Palfium was made available.
Anazodo already had convictions for illicit activities concerning controlled prescribed drugs. Mr Welch, the father of four children, died at his home in Eltham, south-east London, from a Palfium overdose in May 1993.