Harvey Weinstein's Health Is 'Rapidly Deteriorating,' Gaining Lots of Weight

Harvey Weinstein's health is failing ... with the disgraced movie producer rapidly gaining weight and suffering from severe tongue inflammation in New York City's notorious Rikers Island prison.

Juda Engelmayer -- a rep for Weinstein -- tells TMZ ... Harvey's health is "rapidly deteriorating in custody," exacerbated by the terrible conditions at Rikers.

We're told Weinstein has gained more than 25 pounds since being transferred back from Bellevue Hospital several months ago ... 19 of those pounds in the last month alone.

This rapid weight gain adds serious risks to his diabetes and heart condition, Juda tells us ... and, compounding his health problems is severe tongue inflammation, making it difficult to swallow, which has spurred real concerns he will choke to death. Weinstein, Juda says, is currently back at Bellevue so doctors can treat his tongue infection.

Juda adds, "Ongoing issues with missed and delayed medications, chest palpitations that go unaddressed, and a lack of support for his serious mobility issues" are also plaguing Weinstein ... amounting to a medical crisis that must be addressed.

In addition, we're told conditions at Rikers are simply awful ... with inmates suffering freezing temperatures, a lack of clean clothes, and inadequate food -- and, all of this is harming Weinstein's health even more.

As you know ... Weinstein has been dealing with health issues behind bars for years -- landing in local Bellevue Hospital multiple times -- dealing with double pneumonia, a leukemia diagnosis, and undergoing heart surgery ... all in the past year.

Weinstein -- who is still protesting his innocence after he was convicted of rape and several other crimes back in 2022 -- has spoken out from jail in recent days, still advocating for himself ... and, throwing himself in the same boat as actor Justin Baldoni. Weinstein inserted himself in the Baldoni-Blake Lively legal battle, accusing The New York Times of cherry-picking information to fit a certain narrative in both of their cases.

Meanwhile, Weinstein is pushing for his rape retrial to begin ... begging back in January, "I want to be out of this hellhole ... I want this to be over with."