BELOVED comedian Rodney Dangerfield got the fright of his life when he began experiencing shortness of breath and was rushed to the hospital terrified he was in the grips of a heart attack.

The 80-year-old comic — star of “Back to School” and “Caddyshack” — has a history of heart problems, and his wife Joan was so worried about his symptoms she drove him straight to Saint John’s Health Center in Santa Monica.

“Rodney was really scared,” revealed a source close to the comedy legend. “He was terrified he was going to have another heart attack. He kept thinking: ‘Oh, God, is this it?'”

The comic’s spokesman Kevin Sasaki told The ENQUIRER, “They gave him an EKG and it came back a little abnormal so the doctor recommended that he have an angiogram.”

That procedure, in which a catheter (tube) is inserted into an artery and guided into the heart, revealed the astonishing cause of Rodney’s problem: His heart medication was giving him “no respect” — he was having a bad reaction.

“They changed his medication,” said Sasaki. “Once Rodney found out what the problem was, he was naturally very relieved and very happy.”

Later that night, Rodney was allowed to go home.

“He’s fine now. The doctors gave him a glowing report from the test,” Sasaki told The ENQUIRER. “I spoke to him the next morning, and he was in great spirits. He’s doing great.”

But when he first arrived at the hospital on May 21, the bug-eyed comedian clearly feared the worst.

“At his age, Rodney was terrified. Chest pains, shortness of breath — the classic heart attack symptoms,” said an insider. “He was pale and trembling. His wife never left his side.”

Added the close source:

“Rodney was getting really worried. But Joan did a great job of keeping him calm. Rodney swears she saved his life.”

The hard-driving funnyman’s hectic schedule may have contributed to his feeling sick.

“He never stops. He’s got a lot going on,” explained Sasaki.

“He’s just completed a movie, ‘Back by Midnight’ with Kirstie Alley, Randy Quaid and Ed Begley Jr. They shot it all over Los Angeles so he had a pretty grueling schedule. Rodney is also finishing his autobiography.”

Last year, the stand-up star suffered a heart attack shortly after celebrating his 80th birthday on the “Tonight Show” with Jay Leno.

Bighearted Rodney is so thrilled to be given a clean bill of health that he just signed to do public service announcements for the American Heart Association.

Explained Sasaki: “He feels after what he’s gone through perhaps he could be of some service and help to others.”