Elvis Presley's former personal doctor, George C. Nichopoulos, died Wednesday at 88 in Memphis, the AP reports. Known as "Dr. Nick," Nichopoulos was Presley's doctor for 11 years before the singer's death from heart disease on Aug. 16, 1977. The Tennessee Board of Medical Examiners later suspended and ultimately revoked his medical license after it ruled he had over-prescribed potentially addictive drugs to 13 patients, including Presley and fellow singer Jerry Lee Lewis. A jury in 1981 acquitted Nichopoulos of criminal charges of indiscriminately and negligently prescribing drugs to Presley. In a 2009 interview, Nichopoulos said, "I don't regret any of the medications I gave him. They were necessities." (More obituary stories.)