Stand-up comics, famously, do not like hecklers.

They ruin shows. They divert from meticulously calibrated jokes. The response to them is often so brutal and hilarious that heckler takedowns is itself a comedy subgenre.

Ken Jeong thought he was being heckled in Phoenix on Saturday when a woman in the third row during his set at the Stand Up Live Comedy Club unmoored the comedian with a disturbance.

Jeong turned to the character he is perhaps best known for: gangster Leslie Chow from the “The Hangover” series. He began to castigate the supposed heckler in the trademark flamboyant voice of Chow.

But then the lights came on, and it became clear the woman was having an apparent seizure, media reports said.

“It got very quiet very quickly,” audience member Heather Holmberg told The Washington Post.

Ed Helms, Ken Jeong and Bradley Cooper star in “The Hangover II”

Then, the actor reverted to his dormant profession: doctor.

Jeong had already brought up his past as a medical professional in his act, Holmberg said, and audience members urged him to help.

“He literally jumped off the stage and ran right over there,” she said.

Jeong, an internal medicine practitioner turned Hollywood funnyman, cleared the area and attended to the woman alongside a medic who happened to be in attendance, Holmberg said.

The woman regained consciousness and returned to her feet, and Jeong stayed with her until an ambulance arrived, TMZ reported.

Audience members were still stunned and confused through the five-minute ordeal, Holmberg said. Jeong returned to the stage after the incident to say he checked her vitals and reassured the crowd.

They met him with a round of applause, Holmberg said.

And in the age of the smartphone, the audience members were restrained and did not appear to record the incident en masse. “They were very, very respectful,” she said.

Jeong’s representative, Michelle Margolis, declined to make additional comments beyond saying the TMZ story was “accurate.”

At least one audience member thought he nailed the performance. “He’s extremely funny, and gracious,” Holmberg said.

Jeong received his medical degree in 1995 from the University of North Carolina at Chapel Hill, though he soon began moonlighting as a comic. A break in a comedy contest led him to Los Angeles, where he performed sets after long days in an HMO clinic, The Washington Post reported in 2011.

By then, Jeong transitioned to acting full time and stole scenes in “The Hangover” series. He also starred in the NBC sitcom “Community.” He leveraged his medical experience in a short performance in the film “Knocked Up” and in his own sitcom “Dr. Ken,” which was canceled after two seasons last year.

Jeong does not practice medicine anymore but is still licensed in California, though his certification expires in July, according to state records.

After Saturday’s incident, it may be time for Jeong to resurrect an old-but-favorite joke.

“What do you call the guy who graduates last in your class at med school?” he asked The Post in 2011.

“Doctor.”