"Michael at one time had an addiction," Dr. Arnold Klein told King. "He went to England and withdrew from that addiction in a secure setting where he went off drugs all together."
Klein said that he knew that while Jackson was on tour in Germany, he was using Diprivan, with the help of an anesthesiologist, to go to sleep at night.
"I told him he was absolutely insane," Klein said. "This isn't a drug you can repeatedly take."
Complete coverage of Jackson's death
When King asked Klein how he thinks Jackson obtained the anesthetic, Klein replied, "The rich and famous can buy anything they want to buy."
Klein saw Jackson the Monday before he died, and said that the King of Pop was dancing in his office.
"He was in very good physical condition," Klein said. "He was mentally aware when we saw him and in a very good mood."
The dermatologist was helping Jackson "rebuild his face" before his fall tour.
"He had severe acne scarring and scarring from a lot of the cosmetic surgery," Klein said. "He looked much more normal … the way he looked at his face, he wanted it to be absolutely perfect."
King asked why Jackson, as an attractive young man, wanted to have so much plastic surgery.
"I don't know why he started," Klein said. "Family members had made fun of the size of his nose. He was very sensitive to that."
King asked Klein if he was the sperm donor for Jackson's three children. Klein said that he has donated sperm to a sperm bank in the past, but, "to the best of my knowledge I'm not the father."
"Here's the most important thing: Michael loved those children as a father … I'm not going to answer that the way you want. The most important is who the father is, who the children want their father to be … how he loved them and they loved him."