Robert Stolarik for The New York Times

A woman in Andrew Plucinski’s office is squealing. “I don’t want to look at it!” She’s lying out on a hospital bed, her legs exposed, an arm thrown over her eyes.

“It’s nothing yet,” Mr. Plucinski says. He is reaching into a jar of water, in which swim 20 or so leeches. When they dart, they look like calligraphic strokes — black and curved, tapered at their tails. Mr. Plucinski plucks one, wraps it in a twist of paper towel, and positions its mouth toward a spot on the woman’s leg. When the leech begins its work — using its 360 minuscule teeth to scissor in — he laughs. “Now we are into business!”

I don’t laugh. I’m next.

At the Silesian Holistic Health Center of New York in Greenpoint, Brooklyn, being peppered with leeches is not an ancient cure to be associated with the Black Plague and the four humors, but rather a modern holistic remedy that involves rubber gloves, swabs of alcohol, and maxi-pads (the only bandage absorbent enough for his tastes). Mr. Plucinski is a certified hirudotherapist — a holistic practitioner who works with leeches — and he claims that the enzymes leeches secrete, which include blood thinners, have healing properties.

“As long as nothing is fractured, broken or torn apart, leeches will fix it,” said Mr. Plucinski, who prescribes leeches for varicose veins and migraines and to his grown daughter in lieu of a root canal.

“She was, ‘Yadda yadda yadda dentist dentist,’ ” he recalled. “I said why don’t you shut up and try a leech?”

Robert Stolarik for The New York Times

On her gums, he put four.

Mr. Plucinski, 55, who is bearish, with a pale, soft face, is the kind of man who got 46 bee stings to cure a bad back — which is to say he is not afraid of a few leeches. But after a ski accident led him to a holistic healer in Greenpoint, who advised leeches for his injured knee, Mr. Plucinski remembers being “stunned.”

“I said, ‘What do you mean, leeches?’ ” he recalled. “ ‘You mean they are those little bugs that eat blood and all that?’ ”

Now he has changed his tune. Sometimes, he does not use rubber gloves — who needs them! — when he dips his hand into the jar. And though he does not name his leeches, he does refer to them in the feminine. Prodding one, he says “She doesn’t want to drink.”

“In Polish, it’s female,” he said. “We have an expression, also, for mother-in-laws.”

Approved by the Food and Drug Administration in 2004 for use as medical devices, leeches have been proven effective in reattachment microsurgery, draining excess blood from limbs whose veins have not fully fused. Though studies have found that leeches can aid arthritis — leading New York’s Beth Israel Medical Center to adopt the experimental use of leeches — scientists note that such studies can never weather a double-blind test. (A control group patient could never not feel a leech.)

In New York, there are only a few practicing hirudotherapists. But some Eastern European communities have historically embraced leeching as a cure-all, and last year, when Mr. Plucinski opened his own practice, he found a customer base that was mostly Polish. “I don’t advertise in the American media,” Mr. Plucinski said, waving his hand. “They’d run it, but they’d say, ‘Oh yuck, this guy is stupid.’ ”

Maybe that is changing. In 2008, Demi Moore announced on David Letterman that in Vienna, she had thrown a couple of leeches on her visage for an anti-aging cure. Rudy Rosenberg Sr., owner of Leeches U.S.A. Ltd., said that report caused a spike in demand. “You don’t know how many calls we got from people after that,” he said, adding that his company supplied leeches only for the F.D.A.-approved use. “I don’t know what they’re doing it for.”

“Leeches were proven to have no effect on people as early as the 1830s,” said Mark Siddall, a researcher at the American Museum of Natural History who studies leeches. He scoffed at the idea that leeches are somehow purifying — secreting an enzyme while removing bad blood and lymph? “How can it possibly do that when it’s only removing stuff?” Dr. Siddall said. “It’s not like it’s removing stuff and putting it back. It completely has been proven not to be effective for anything like that.”

Dr. Siddall also dismissed the claim that leeches secrete a painkiller that makes their application less unpleasant. “Complete and total hooey,” he said. “It’s one of those notions that’s been repeated often enough to have the status of fact, for which there is no scientific evidence whatever.”

I learn that first hand.

As I sit back in the black leather chair with my leg resting on a paper towel to sop up excess blood and lymph, Mr. Plucinski places a leech about a centimeter from a raised, bluish vein that he says in time will become varicose.

At first, the leech does not want to bite. Mr. Plucinski says my skin has toxic residue from soap. That, or it is going to rain — he says they can sense bad weather.

“Leeches sense the emotional stage of the client,” Mr. Plucinski says. “It can tell if the client is hysterical, scared.”

Rejected by a leech: a new low.

So Mr. Plucinski plucks a leech from a tank of older, bigger leeches (they are hungrier, with lower standards, like men at closing time) and plops it down.

Robert Stolarik for The New York Times

The pain! It’s like getting a tiny tattoo — just a few needle-pokes wide. I squirm, clench my jaw, and in the interest of journalism, attempt to keep my hands off my eyes to watch it undulate. It is like the throat of a man drinking Gatorade.

“It’s slowly sipping a margarita,” I joke.

“More like a bloody mary,” says Mr. Plucinski, coolly, as if he has said that before.

After an hour, I’m wondering when this will end. “It comes to the point where they’re so full they’ll drip from the mouth,” he says. To get the leech off, Mr. Plucinski has to thrum it on the back so its skin ripples like a water balloon and it rolls off. Then he picks it up and dumps it in a jar of alcohol — instant death.

How sad. Starved for a year, fed a sumptuous Thanksgiving feast, and summarily executed. I ask Mr. Plucinski if he ever felt bad.

Mr. Plucinski looked into the alcohol, where the leech roiled, and said, “You can’t get too attached.”

The Silesian Holistic Health Center of New York is at 231 Norman Avenue in Brooklyn. Its phone number is (646) 460-4212.