An East Village dog walker traded a Manhattan fashionista’s beloved pit bull for angel dust, the devastated owner charges in a new lawsuit.

Sugar, a 4-year-old brown and white rescue dog, has been missing since Feb. 23, when canine caretaker Tommy Doerr claims to have had “an unexplained psychotic episode” and can’t remember what happened to the dog, according to court papers.

Sugar became a social-media sensation as owner Morgan Bogle used Facebook, Twitter and Instagram — plus thousands of posters and even a Seventh Avenue billboard — to spread the word about her lost companion, creating the viral hashtag #FindSugarNYC along the way.

But Bogle doesn’t buy Doerr’s story of a breakdown, according to a Manhattan Supreme Court lawsuit she filed against him.

Doerr, 46, was “detained by the police who had allegedly searched him and found him in possession of a controlled substance, believed to be PCP,” Bogle claims in court papers.

She “has also been told . . . that [Doerr] ‘traded’ Sugar to some drug dealers in return for PCP or sold Sugar in order to obtain money to buy drugs,” court papers state. “Morgan believes that her best friend and beloved pet was sold by Doerr to be used in connection with dog-fighting or traded for controlled substances.”

Bogle “is rapidly losing hope that Sugar will ever be found alive,” court papers add, despite the posted $10,000 reward. Her lawsuit, filed last month, wants a judge to order Doerr to return Sugar or pay $10,000 in damages.

No arrests have been made, ­according to the NYPD.

Doerr was not on drugs, his lawyer insists.

“I can tell you there was a drug intake [at the hospital] and it was completely negative, which proves that any allegation that he was on any kind of drugs is completely false,” attorney Mel Ginsburg told The Post.

“There’s a lot of completely false allegations being made about this case,” Ginsburg said. “Nobody’s going to fake going into the hospital. There’s no intent here.”

The attorney doesn’t deny Sugar was lost on Doerr’s watch but refused to clarify his client’s medical issues or the circumstances of Sugar’s disappearance.

“Things happen that people don’t remember,” he said.

When confronted Saturday by The Post, Doerr denied his identity and refused to answer questions about Sugar or his alleged drug use.

Doerr had been Sugar’s dog walker for three years without incident before Bogle left on a business trip to London. He was supposed to be caring for Sugar inside his East 26th Street apartment, but witnesses said they saw Doerr on Feb. 23 kicking Bogle’s front door and shouting.

Bogle at the time said a neighbor sent her a text message and she sent a friend to Doerr’s home, where he was found hiding behind a trash can and “acting strange.” The pal called cops.

From Bellevue Medical Center, Doerr gave Bogle permission to go into his home, where she found Sugar’s collar and sweater, she claims. The dog was gone.

The dog walker has countersued Bogle, accusing her of defamation because of the “false” drug allegations. Doerr also claims a pet detective hired by Bogle treated him “in a most abusive and intimidating manner” and told Doerr he should kill himself, according to court papers.

Additional reporting by Melkorka Licea