Funnyman Chevy Chase has dropped more than 40 pounds in just months – and medical experts warn it could be a diet for disaster!

The 71-year-old “Saturday Night Live” legend had ballooned to more than 300 pounds and was reportedly rushed to the hospital with heart attack symptoms just five months ago.

Experts say Chase’s dramatic weight loss – as seen in these exclusive photos obtained by The National ENQUIRER – could be due to liposuction, lap band surgery or extreme dieting, and could kill him!

“Rapid weight loss like this, especially if it’s unsupervised, can provide a significant shock to the body,” said Dr. Stuart Fischer, a specialist in internal medicine, who has not treated the comedian.

The 6-foot-4 Chase – star of the classic comedy “Caddyshack” and the “National Lampoon’s Vacation” films – suffered severe breathing problems during the emergency room episode in late April.

The actor was told that he might be risking his life if he left the hospital, but was allowed to leave after a series of tests.

Experts who have reviewed the images of a slimmed-down Chase – snapped Oct. 6 on the set of the upcoming big-screen “Vacation” reboot – speculate that he may have taken one of several dangerous shortcuts to lose weight so quickly.

Cosmetic surgeon Dr. Yoel Shahar, who has not treated Chase, said: “Liposuction is a clear possibility but, at his age, is dangerous and carries several risks. The fat will also reappear in other parts of the body.”

Dr. Fischer agreed, adding: “It’s a bad choice for someone with his level of obesity and risk of coronary artery 

Another alternative that Chase may have chosen is lap band surgery, experts say.

“It’s a proven solution, but only if he’s willing to change his eating habits as well,” pointed out Dr. Karin Hehenberger, a diabetes expert who has not treated Chase.

Drastic dieting is another option, but the experts warn it would have been the most dangerous route.

“Extreme dieting leads to dehydration and malnutrition,” cautioned Dr. Hehenberger.

“This leads to disturbances in electrolytes and heart rhythm problems, which brought him to the ER in the first place.”

Chase’s yo-yo dieting is a recipe for disaster, added Dr. Fischer.

“His weight swings and the metabolic havoc they cause may lead to diabetes, hypertension and high cholesterol,” he explained.

“He is at risk for stroke, severe kidney disease and a heart attack every minute of his life.”