Hospitalized former world heavyweight boxing champion Muhammad Ali was diagnosed today as suffering from "Parkinsonism," or minor symptoms of Parkinson's disease.

Ali, 42, apparently does not have Parkinson's disease (a degenerative brain disorder) "per se," and experts believe his condition can be controlled by medication, said Martin Ecker, one of his physicians, in a telephone interview with the Associated Press. Ali was given test medication as treatment today.

"He's not in any danger. It's not a fatal disease," said Ecker, medical director of Ali's boxing management company. "You don't die from what he has and I feel very optimistic that what he has can be controlled by medication."

In an interview today at Columbia-Presbyterian Medical Center, in which his speech was slow and slurred, Ali said it was possible boxing had caused his problems, but he did not regret fighting because of the good it allowed him to bring to other people.

"I've been punched a lot of times," said Ali. "I've been in the boxing ring now for 30 years and taken hard punches in fights and also in training preparing for the fights, so there's a great possibility something could be abnormal."

Ali said he expects to be hospitalized two more days.

Ecker, a diagnostic radiologist who is a consultant on Ali's case, said drugs were being administered to the former champion "to see if they help him and how much they help him."

Ali, complaining of slowed motion and slurred speech, underwent five days of tests at Columbia-Presbyterian this month before leaving for Europe Sept. 11. He returned Tuesday for more tests and treatment.

His longtime adviser, Herbert Muhammed, said doctors determined from the first set of tests that Ali was suffering from Parkinson's syndrome and, possibly, a form of hypoglycemia (low blood sugar).

The former boxer was notified of the test results while he was in West Germany and was given medicine there, "but it was too strong and he started vomiting," Muhammed told United Press International in a telephone interview from Chicago.

Ali may have been suffering from the problem, the cause of which is generally unknown, for as long as a decade, but obvious symptoms surfaced only in recent years, Muhammed said.

"We have been having problems with Ali knowing he was getting tired," Muhammed said. "He noticed his speech started to slur, then he noticed his hands started shaking."

Because his condition apparently was not worsening and he lacked classic symptoms, doctors ruled out both Parkinson's disease and "the punch-drunk syndrome," caused by repeated blows to the head, Ecker said.

Ali's speech has been slurred -- at times unintelligible -- for about two years. "I'm in good shape," he told well-wishers afer arriving at Kennedy International Airport Tuesday night. "I'm a little tired, but I'm in good shape."

Ali is "not worried. He's very calm and very accepting of what he has," Ecker said.

Ali is the only fighter to have won the heavyweight boxing championship three times, in a 21-year career that began in 1960. He was stripped of his title in 1967 when he refused to be drafted into the Army; he won it back from George Foreman and later lost and won it against Leon Spinks.