Toronto physician Fred Hui believes that administering vitamin C intravenously is a treatment worth trying.

The advantages: It's cheap, available and relatively free of side effects.

The disadvantages: Nobody knows if it works.

Nevertheless, Hui would like to see people who are quarantined taking vitamin C in high doses.

And he'd like to see people admitted to hospital for the pneumonia-like virus treated with the vitamin intravenously while also receiving the usual drugs for SARS.

Hui earned his M.D. at the University of Toronto in 1979, and has since studied traditional Chinese medicine in Beijing.

"I appeal to hospitals to try this for people who already have SARS," says Hui. "I urge people who have come into contact with someone who has SARS to try it."

Members of the public would also do well to build up their levels of vitamin C, he says.

Vitamin C is underused in orthodox medicine, Hui believes. He says it hasn't been supported by research and promotion because it can't be patented.

Hungarian biochemist Albert Szent-Gyorgyi first isolated vitamin C in 1928, and later won a Nobel prize for his discoveries.

American physician Linus Pauling, two-time Nobel prize winner, studied the vitamin's importance to the immune system and suggested in 1970 that people taking higher doses than those officially recommended could prevent the common cold, or shorten its duration. The medical establishment reacted with strong opposition to his ideas, but the public was more receptive.

Vitamin C is a powerful natural antioxidant, an important ingredient for the synthesis of collagen, and essential for the production of white blood cells, antibodies and other disease-fighting elements. During illness, the body's vitamin C levels are depleted.

Because SARS is a virus, Hui says, the effects of vitamin C should improve the body's defences against it. And since it has a low cost, is universally accessible, and is easily tolerated by the body, there is nothing to lose in trying it as a treatment for SARS.

Vitamin C is water soluble, he notes, so the body excretes any excess and no toxicity accumulates. No dose of vitamin C high enough to be toxic has yet been discovered.

"This is one of the most harmless substances there is," Hui states. "There used to be concern about kidney stones, but that was theoretical. It was never borne out in an actual case."

The doses needed to be effective vary from individual to individual, he says, noting that smokers, elderly people, diabetics, chronic drinkers and people who are ill or are in high stress situations need higher doses. Pollution also increases the amount of vitamin C needed.

Hui says he believes everyone could benefit from at least one gram a day of vitamin C, and more for most people. The recommended daily allowance — the level needed to keep from getting scurvy — is 75 mg for adult men and 90 mg for women.

Hui says he routinely takes six grams of vitamin C a day, spread throughout the day. He also recommends high doses to relatives, friends and patients.

When someone takes a dose higher than the individual's body needs, Hui says, the digestive system reacts by producing loose stools or diarrhoea. He recommends that people increase the dose until they experience loose stools, and then cut their vitamin C intake back by one measure to find the exact dose most useful to them at that time.

One possible nuisance side effect, particularly for those with sensitive stomachs, Hui warns, is an acidic stomach. To avoid this, he recommends taking the vitamin C with food, or taking it in a form buffered with minerals. Buffered vitamin C is available in tablets, capsules, or granules that can be mixed in a glass of water of juice.

The amounts of vitamin C Hui recommends are too high to be taken in food.

David Jenkins, professor of medicine and nutritional science at the University of Toronto and a physician at St. Michael's Hospital, says he hadn't heard of using high-dose vitamin C to fight SARS, but he finds the idea intriguing since some studies have found the vitamin effective with the common cold.

"The common cold is a coronavirus, and SARS is a coronavirus so they are the same viral type," he observes. "In the absence of a vaccine, this sounds like an interesting approach."

Jenkins doubts that the whole medical establishment will greet the idea with enthusiasm. "Many of my colleagues grumble even about following Linus Pauling up to 10 grams a day," he says. "They're worried about the acid load. And anyone who takes high doses of vitamin C and stops cold turkey can become deficient, even with normal intake. A gradual cutback is okay."

He says he's never heard of anyone taking doses as high as 100 or more grams a day as recommended by some proponents of the use of vitamin C for people with active SARS.

"That could lead to torrential diarrhoea," he warns. "Anyone who tries this should only do it under medical supervision, and should use caution.'

Jenkins says he wouldn't automatically throw cold water on the idea and his own position is one of cautious interest. "This is new stuff for many of us," he adds. "That's an awful lot of C."

Humans are one of the few animal species, like other primates and guinea pigs, whose bodies can't produce their own vitamin C, so need to get it through diet.

Hui says he has found intravenous vitamin C effective in his medical practice with patients who have viral illnesses.

"For people with infectious mononucleosis, instead of letting them take six months to recover, I give them a vitamin C drip and they recover within days," he says.

"When a patient comes in with a bacterial infection, that calls for antibiotics. When the signs point to a virus, I recommend pumping up the oral vitamin C. A low dose just doesn't have the right mechanisms to be effective. A high dose of vitamin C produces hydrogen peroxide, which kills germs."

When Hui started speaking out about the benefits of high doses of vitamin C, he soon heard from the outspoken California physician Robert Cathcart, one of the leading authorities on the clinical use of this vitamin. Cathcart maintains that when vitamin C isn't widely effective in cases of viral infections like SARS, it is because doses are not high enough.

"I can tell you that SARS will be cured by massive doses of intravenous sodium ascorbate (vitamin C)," he declares on his Web site. "What is not getting across, for whatever reason, is that the amount of intravenous sodium ascorbate necessary to take out SARS is truly massive, like perhaps 120 to 180 grams a day or more .... Let us not fool around with phony low doses that will not work."

He complains that some people refer to doses such as four grams as megadoses. "For these purposes, four grams is ridiculously inadequate."

Hui says it's the right time for hospitals, quarantined people, and anyone concerned by the present public health situation, to try high dose vitamin C.

"This may be the key to winning the fight against SARS," he says.

Among many Web sites with vitamin C information is http://www.garynull.com/documents/vitaminc.htm.