The disgraced former Hollywood film producer was reportedly suffering high blood pressure and heart palpitations on his way to jail following his conviction on Monday.
A spokesman for Weinstein later said he was diverted to Bellevue Hospital in Manhattan, which has a unit that provides medical care for prison inmates.
It comes after he was found guilty of sexually assaulting former production assistant Mimi Haleyi in 2006 and raping a woman in 2013.
Weinstein's spokesman said he did not know why the former movie mogul went to Bellevue or how long he would be there. A number of US news outlets reported that he had complained of chest pains.
His attorney Donna Rotunno told CNN he was suffering heart palpitations and high blood pressure.
The once-powerful film producer was found guilty of two charges following a landmark trial which involved harrowing and excruciatingly graphic testimony from a string of accusers.
But the 67-year-old was acquitted on the most serious charge - predatory sexual assault - which carried a potential life sentence. He was also cleared on first degree rape.
Weinstein, who was ordered to go to jail immediately after the verdicts were given, now faces up to 25 years in prison. He will be sentenced on March 11.
Though Judge James Burke cautioned the jury not to see the case as a referendum on #MeToo, the case will be seen as a milestone for that movement, which has inspired women to go public with misconduct allegations against powerful men.
Actress Rose McGowan, who had accused Weinstein of rape, wrote on Twitter following the conviction: "Today is a powerful day & a huge step forward in our collective healing."
A statement for the #MeToo movement said: "The jury worked with an incredibly narrow and unjust set of laws governing sexual assault, and though he was not convicted on all counts, Harvey Weinstein will have to answer for his crimes."
Weinstein faces up to 25 years in prison on the sexual assault conviction. He was also convicted of third degree rape - sexual intercourse without consent - which carries a prison sentence of up to four years.
The jury of seven men and five women acquitted Weinstein on the most serious charges, which carried a potential life sentence.
Weinstein still faces sexual assault charges in California, which were announced just hours after his New York trial began on Jan. 6. Dozens of women have also filed civil lawsuits against him.
More than 80 women, including famous actresses, accused Weinstein of sexual misconduct stretching back decades. He denied the accusations and said any sexual encounters were consensual.
Manhattan District Attorney Cyrus Vance said at a news conference: "It’s a new day because Weinstein has finally been held accountable." He praised the jurors, saying: "Your verdict turned a page in our criminal justice system.
"To the survivors: I owe and we owe an immense debt of courage to you," Vance said.
While he did not testify, his lawyers contended that any sexual contact was consensual and that his accusers went to bed with him to advance their careers.
The defence seized on the fact that two of the women central to the case stayed in contact with Weinstein, and also had sex with him, after he was alleged to have attacked them.
Ms Haleyi testified that she had sex with him two weeks later, while the rape accuser whose name was withheld said she had a sexual encounter with him more than three years afterwards.
During closing arguments, Weinstein lawyer Donna Rotunno charged that Weinstein had become "the target of a cause and a movement" and asked the jury to ignore "outside forces".
The case against the producer was essentially built on three allegations: that he raped an aspiring actress in a New York City hotel room in 2013, that he forcibly performed oral sex on Ms Haleyi and that he raped and forcibly performed oral sex on Sopranos actress Annabella Sciorra in her apartment in the mid-1990s.
Many of Weinstein's accusers described him as a person who would incredibly charming at first, making jokes and showing interest in using his immense power to help their careers.
But that was an act, they said, meant to gain their trust and get them to a place - often a hotel room or an apartment - where he could violate them.
Several women testified that Weinstein excused his behaviour as the price for getting ahead in Hollywood.
One said that when she laughed off his advances, he sneered, "You'll never make it in this business. This is how this industry works."
During his trial, Weinstein often appeared feeble, entering the courthouse using a zimmer frame and sometimes leaning on his lawyer for support.
Critics accused Weinstein of playing up medical problems to win sympathy but Weinstein said he had back injuries.
Weinstein now faces charges in Los Angeles. In that case, announced just as the New York trial was getting under way in January, authorities allege Weinstein raped one woman and sexually assaulted another during Oscars week in 2013.
One of those women testified as a supporting witness at the New York trial.
Weinstein was arrested in May 2018, seven months after The New York Times and The New Yorker exposed his alleged misconduct in stories that would win the Pulitzer Prize.
He had denied the allegations and said any sexual encounters were consensual.