VANCOUVER, British Columbia (CNN) -- I didn't know quite what to expect when I entered the injection room at Insite, the world's busiest supervised drug clinic.
Lorraine Trepanier says she's a longtime user of illegal drugs, such as cocaine and heroin.
Inside the Vancouver facility, I found more than a dozen people taking illegal drugs, such as heroin and cocaine, under the watchful eye of trained nurses. These drug users were among the more than 700 people who visit the facility every day, bringing their drugs with them.
Insite's goal is to reduce the risk of overdose and limit the spread of diseases like HIV by giving addicts clean needles and a safe place to use them.
"People need to be kept alive long enough in order to get treatment," said Liz Evans, a nurse and founder of Insite.
The clinic, which is sanctioned by Vancouver's health department, opens each day at 10 a.m. and stays open until 4 a.m. the following day. Many of the people in the clinic on the day we visited had tattered clothes, missing teeth and glassy eyes. They swayed as they struggled to keep their balance. Watch people shoot up in the Vancouver clinic »
Outside of the clinic, police patrolled the streets to keep people from buying and selling illegal drugs. Inside, patrons were given access to Insite's clean needles, injection booths and nurses. Similar facilities can be found at 65 locations in eight different countries.
San Francisco health officials recently held a day-long conference on the Vancouver drug clinic, with an eye toward possibly opening a similar one. But San Francisco Mayor Gavin Newsom said the city is unlikely to do so.
"You had a lot of health officials there that did participate in the pros and cons. But my director of the department of public health doesn't feel the city should move forward," Newsom said.
Defenders of the Vancouver clinic say more than two dozen peer-reviewed studies have shown its benefits. One study found a 45 percent reduction in public drug use as a result of the clinic; another showed 33 percent of addicts are more likely to go to detox after using Insite.
Dr. Thomas Kerr, a University of British Columbia research scientist who has studied the program, believes Insite benefits the wider community.
"In the absence of such a facility, not only would [drug users] be high out on the street, but they would be leaving their syringes in school yards, in parks and on city streets," Kerr said.
Dr. David Murray, chief scientist for the White House Office of National Drug Control Policy, opposes opening drug injection clinics in the United States. He believes they do little to help addicts overcome their additions.
"It is a cruel illusion because they are still addicted, trapped, trying to get out and dying by the virtue of the drug itself," he said.
Nurses at the Vancouver clinic say they get all kinds of people using their facility, from an old grandma who comes to inject her pain medication to men in business suits hiding their addictions from their families.
At the clinic, we met Lorraine Trepanier, 50, a longtime drug user. Trepanier said she used to sell her body for drugs, but now relies on a friend to give her the $20 she uses every day to buy cocaine and heroin.
"I get up in the morning and I make sure I have one down or half a down," she said, referring to her heroin fix. Trepanier believes Insite has helped keep her alive by giving her a supervised setting in which she can take drugs.
Evans and other operators of Insite say that rather than chase addicts from corner to corner and alley to alley, it is more effective to encourage them to use their drugs in a supervised setting.
In the more than four years Insite has been open, there have been roughly 800 overdoses at the facility, but there have not been any deaths. When someone does overdose, nurses try to revive them. If the drug user is in critical condition, they are sent to a hospital.
Trepanier doesn't care what critics have to say about Insite. All she wants is a chance to get her next fix in a clean facility, until the day she finally works up the willpower to kick her addition.
"I don't want to be down here all my life," she said. "I don't want to be chasing this all my life." E-mail to a friend