Arthur Janov, a California psychotherapist variously called a messiah and a mountebank for his development of primal scream therapy — a treatment he maintained could cure ailments from depression and alcoholism to ulcers, epilepsy and asthma, not to mention bring about world peace — died on Sunday at his home in Malibu, Calif. He was 93.

The office manager of his organization, the Janov Primal Center in Santa Monica, Calif., confirmed the death.

A clinical psychologist, Dr. Janov conceived primal therapy, as his method is formally known, after an epiphany in the late 1960s. He introduced it to the world with his first book, “The Primal Scream,” published by G. P. Putnam’s Sons in 1970. The book attracted wide attention in newspapers and magazines and made a celebrity of Dr. Janov, who became a ubiquitous presence on the talk-show circuit.

Primal therapy became a touchstone of ’70s culture, especially after it drew a stream of luminary devotees to Dr. Janov’s Los Angeles treatment center, the Primal Institute, among them John Lennon, Yoko Ono, James Earl Jones and the pianist Roger Williams.