A disgruntled businessman allegedly hacked into the computer of his Manhattan dermatologist ex and stole her patients’ data then taunted her in a profanity-laced tirade.

Kenneth Asher, 50, the president of the IT consulting company VP Vision, called Dr. Robin Borkowsky a “f–ktard” and threatened, “Email to patient population going out today…working on a text blast too.”

He followed up with the names of several of Borkowsky’s patients and their birthdays from her practice at 21st Century Dermatology in Midtown.

“[Patient name] remember him?” Asher allegedly wrote Brokowsky, 48, in the July 9 message. “He just turned 67 in March.”

He added, “Tell your attorneys I have far more information on you than you do me.”

Manhattan prosecutors said Asher’s taunts grew increasingly bitter.

“Maybe that rapist from the Upper West Side will find you tonight,” he wrote.

Asher was arrested July 11 on charges of computer trespass, unauthorized use of a computer and aggravated harassment.

Defense lawyer Michael Bachner said the former couple had been dating for two years and had an acrimonious split on their way home from the Hamptons.

The attorney countered that Asher only had access to the computer and patient files because she had asked him to do IT work for her practice.

“The allegations that Mr. Asher without authorization accessed computer information is utterly false,” Bachner said.

Asher has had prior legal entanglements, according to prosecutors.

ADA Michael Rivet said he had “an extensive out-of-state record,” including a 1992 federal conviction for computer hacking.

Asher was charged with wanton endangerment for allegedly piloting an airplane that crashed into a lake, killing his passenger in 1998, court records show.

Judge Heide Cesare issued an order of protection in Borkowsky’s favor, but the two might have trouble avoiding each other as they live on the same street.

Borkowsky didn’t immediately respond to requests for comment.