Where to get it is passed through word of mouth and on the expat message board on HeyKorean.com.

At the clinic in Flushing where Ms. Jang said she and her friends went regularly for treatments, three beds lie behind a blue curtain in an alcove where, a receptionist explained, patients relax while IV treatments are administered. Dr. Weining Liang, who runs the clinic, said he only performs IV treatments when a patient is very ill. As he spoke in his office, a few steps away attendants escorted patients into the alcove and drew the curtains around them.

Dr. Liang said he could not recall Ms. Jang being a patient, nor her being taken by ambulance from his clinic. He denied that the clinic provided IVs on demand. “It’s not true,” Dr. Liang said, before telling a reporter to leave his clinic immediately.

Ms. Jang is suing the clinic and a doctor there, George Mang, on grounds that the care she received was negligent and deviated from standard medical practice. The suit, filed in State Supreme Court in Queens, says that Ms. Jang was a victim of malpractice, and claims that no one asked her why she was sick, that the clinic merely took her cash and gave her an IV solution.

“They need to explain what happened,” said Jeffrey Kim, a lawyer for Ms. Jang. “People don’t normally go into a clinic and come out with symptoms that result in amputation. These clinics that are in the Korean community, they need to diagnose patients properly, and not take a patient’s word that that’s what they need and just administer this stuff to make a quick buck.”

Reached by phone, Dr. Mang declined to comment.

Jungeun Park, 72, a friend of Ms. Jang’s, said that when she had a nasty cold, a nurse who attended her church administered a drip at her home. Treatments were perfunctory: “She put a needle in my arm” and left, Ms. Park said. “I just took it off when it was done.”

Since Ms. Jang’s amputations, Ms. Park has forsworn drips, as has much of the parish, she said.

On Jan. 3, after 11 months at New York Hospital Queens, Ms. Jang will be taken by a medical transport vehicle to Kennedy Airport, and will head home to Seoul, South Korea, where her husband lives, she said. Her lawyer said her hospital bill, which she cannot afford, has not yet been paid. The hospital declined to comment, citing privacy rules.

On Northern Boulevard in Queens, at Smile Pharmacy, a clerk said the bags of solution ran for about $20. But when asked later about selling them without a prescription, Tae Lee, the pharmacy owner, said the clerk misunderstood the request.