Jeff Conaway, 60, an actor who came to fame in the late 1970s as a high school tough in the movie musical “Grease” and in the TV series “Taxi,” but who was known in recent years for his appearances on “Celebrity Rehab With Dr. Drew,” died May 27 at a hospital in Encino, Calif. He had complications from pneumonia.

He was taken off life support after arriving unconscious at Encino Hospital Medical Center on May 10, the result of “just too many prescribed drugs,” said his sister Carla Shreve. He had been in a medically induced coma.

Mr. Conaway had appeared in movies and on television and in the Broadway production of “Grease” before the movie version starring John Travolta and Olivia Newton-John was released in 1978.

Mr. Conaway played Kenickie, the high school pal of Travolta’s Danny Zuko.

“I got so many hickeys, people will think I’m a leper,” Stockard Channing’s Rizzo tells Kenickie at one point, examining her neck in a compact mirror.

“Cheer up,” Mr. Conaway’s character memorably replies. “A hickey from Kenickie is like a Hallmark card.”

Later the same year, Mr. Conaway began playing Bobby Wheeler, the cab-driving struggling actor in “Taxi.”

The series about a group of New York cabbies, whose ensemble cast included Judd Hirsch, Danny DeVito, Marilu Henner and Tony Danza, ran until 1983.

Although the show gave Mr. Conaway continued national exposure, he broke his contract and quit after three seasons, having reportedly grown tired of being typecast as a “blond bimbo” and the butt of struggling-actor jokes.

“In ‘Taxi,’ I kept doing the same scene for three years,” he told the Toronto Star in 1989. “I was underused.”

He later said the experience made him “very depressed,” but he had little success with other projects. After roles in two short-lived TV series, “Wizards and Warriors” and “Berrenger’s,” he had a part in a 1985 Broadway rock musical “The News.” It closed after two days.

He later appeared in the soap opera “The Bold and the Beautiful” and the 1990s sci-fi TV series “Babylon 5.” TV guest shots and roles in films and TV movies followed, as did stories of his substance abuse.

After failed attempts at sobriety as early as the 1980s, Mr. Conaway appeared with eight other celebrities on the premiere of VH1’s “Celebrity Rehab with Dr. Drew” in 2008. He was so intoxicated the morning he checked in that subtitles were required to translate his slurred speech.

“Celebrity Rehab” added a new dimension to Mr. Conaway’s faded celebrity.

“Everywhere I go, people say, ‘I watched that show. I was rooting for you, man,’ ” he told the News Journal in Wilmington, Del., in 2008. “It’s nice to know people care. I hope it helped some people.”

In a Los Angeles Times interview in January, Mr. Conaway said he had ramped up his behavior for the camera.

“We all knew we were on TV,” he said. “Sometimes we would go a little bit further than maybe we normally would. You can’t help it. There are cameras sitting in front of your face.”

Mr. Conaway was back on “Celebrity Rehab” for its second season in late 2008.

Jeffrey Charles William Michael Conaway was born in New York City on Oct. 5, 1950.

His acting career was launched in 1960 when his mother, an actress, brought him with her to an audition for the Broadway drama “All the Way Home,” in which director Arthur Penn cast him as a young Southern boy.

He said he began taking drugs when he was in a rock band in his teens. After a year at the North Carolina School of the Arts, he enrolled at New York University.

He understudied a number of characters in “Grease” on Broadway and, shortly before graduating, took over the lead role of Danny Zuko.

Mr. Conaway was once married to Olivia Newton-John’s sister, Rona.

Survivors include his wife, Kerri Young Conaway; two sisters; and a stepson.

— Los Angeles Times