Rapper Eminem performs at a concert celebrating the launch of the video game "DJ Hero" in Los Angeles on in this June 1, 2009 file photo. Photoby AP
John says Eminem is succeeding in his well-publicised battle against substance abuse.
John told BBC Radio Saturday that as a recovered drug abuser he is happy to help people if they want the assistance but drugs make people so cocky and arrogant that they often reject help.
Eminem has written about his substance abuse problems in the past.
