Burt Reynolds is in such agony from back problems that he’s been undergoing risky spinal injections to ease his pain.

The 66-year-old actor revealed that he’s had epidural anesthesia, a treatment often used in childbirth in which pain control drugs are injected directly into the space around the spinal cord.

During his one-man show — “An Evening With Burt Reynolds” — in mid-November in Stuart, Fla., his discomfort was so apparent to the audience the actor finally admitted he needed the pain blocker to help him get through his performance.

“Burt was obviously in pain,” theater critic Hap Erstein told The ENQUIRER. “Several times he got up and walked around the stage, clearly trying to walk it off. And when he sat down again, he did so very gingerly.

“It was obvious to everyone in the audience, and I think that’s why he finally made an announcement about the epidural anesthetic. But he was able to make a joke about it — he got a big laugh when he said, ‘Now I’m ready to have a baby.’ “

The treatments are not without risk. Epidurals have been successfully used for women in childbirth for many years, but experts warn they can cause infection or bleeding in the spine — or even numb muscles so much the patient can’t move or walk.

“It’s a case of Burt’s macho past catching up with him,” a source told The ENQUIRER. “He was a college football star and later he loved doing his own movie stunts. Now it seems like the beating his body took is coming back to haunt him.”

This is not the actor’s first battle with pain.

In 1984, when he was filming “City Heat” with Clint Eastwood, he was hit over the head during a fight scene with a wrought-iron chair. The head and jaw injuries left him in so much agony that eventually he became addicted to the sleeping pill Halcion.

“The pain was worse than a migraine,” he said. “I would get out of bed and take five pills. Five or six hours later the pain was so bad I’d take five or six more.”

Eventually he was taking 50 Halcions a day — and when he tried to quit cold turkey, he fell into a coma during which he came close to death. He finally kicked the habit with the aid of his doctors.

“Now Burt is living with pain again,” said the source. “But he’s incredibly brave — he just gets on with his life without complaining.”