In China, there has always been a fine line between food and medicine. Ginger with crab may be a perfect flavor combination, but ginger also happens to be cited in the ancient Chinese pharmacopeia as an antidote to shellfish poisoning. Water chestnuts, considered binding, are fed to children who swallow coins or other metallic objects. Even soy sauce is thought to be a healing salve for burns, eczema and leprous sores.

While some modern Chinese chefs are aware of the healthful properties of ingredients, it's not an overriding concern when they cook up a dish. However, for the first time outside Chinese borders, a restaurant devoted solely to Chinese medicinal principles opened recently in San Francisco's Chinatown. Small and bright, with formica-topped tables, it's called the Emperor Herbal Restaurant, and its offerings are unusual indeed.

For a beautiful complexion, there's "Pearl Soup" made with real ground pearls, wild ginseng and white tree fungus. Insomniacs are encouraged to try something called "Sweet Dreams." For forgetfulness or headaches, one can order a dish labeled somewhat cryptically, "Gone with the Wind." And to maintain youthful beauty, women should eat "Queen's Secret," which lists among its ingredients, snow lotus, deer antler and the meat from a black-skinned chicken.

The Chinese have been brewing up herbal concoctions for centuries, and herbal shops have long been a fixture of Chinese communities, but the idea of an herbal restaurant is relatively new. Thirty years ago in Chengdu, Sichuan Province, a popular herbal store opened an adjoining restaurant where people with high blood pressure or sore joints, or those who just wanted to stave off skin wrinkles could order dishes tailored to their needs. The idea spread rapidly to other Chinese cities.

Alan Lau, managing partner of the Emperor Herbal Restaurant, also runs Mayway Corp., the biggest wholesaler of Chinese herbs in North America. Lau sells to Chinese herbalists in New York, Los Angeles and London, and he has offices in Hong Kong. His catalog lists among its hundreds of entries -- most of them roots, barks and berries -- scorpion, at $28 an ounce, real musk for $375 an ounce, and silkworm excrement, a bargain at $3.50.

Lau says he can't make medicinal claims for his restaurant dishes under U.S. federal law, just as he can't for the herbs he sells next door at his China Herbs and Native Produce Company, one of the best stocked shops this side of Hong Kong. The offerings at the restaurant are, however, the same tonic combinations prescribed for centuries in China. For the uninitiated, the employes explain what each dish is supposed to be good for, and each menu entry lists every ingredient in English -- often its Latin or pharmaceutical name -- and in Chinese.

Lau says his restaurant is for anyone interested in good health. "You don't have to be diabetic to eat 'Spring Fountain,' " he explains. Although the Chinese believe its ingredients -- mulberry bark, corn silk, wild ginseng, lamb, etc. -- cut down blood sugar over time. "The herbs we use aren't like chemicals; there are no side effects. "We have dishes for high blood pressure {New Empathy}, the digestive system {Clear River}, women's problems, anti-aging, memory and to keep the arteries young and soft."

Lau arranged for chefs trained in herbal cookery from Hangzhou, Guangzhou and Beijing to spend time working with his cooks before and after the restaurant opened. Many of the ingredients used will be familiar to anyone who frequents Chinese restaurants. "We opened this restaurant to educate the American people who think herbal food tastes terrible," says Lau. "This isn't so."

Whether or not they cure what ails you, the main entries under "Herbal Food," are unusually flavored and nicely presented in earthenware or ceramic crocks or bowls. Because it takes the herbs time to brew, most are slow cooked, often steamed in some kind of broth. Prices range from $3.75 for "Vigorous Strength" -- good for the kidneys and lower back -- to $12 for "Sea Treasure" which contains such delicacies as shark's fin, abalone and sea cucumber; most dishes are around $4.75.

The "Lover's Soup" on the menu at $5.75 -- a supposed aphrodisiac whose name has been prudently changed from its original "Deep Lover" -- contains "dragon bone" which Lau says is dinosaur bone, "important for functioning of the male sex organ." He acknowledges that some people get upset that Chinese herbal shops are buying the fossilized bones of those beloved, extinct creatures. "But," he adds, "the price is still only $6 or $7 a pound; they got lots of them."

The Emperor Herbal Restaurant welcomes vegetarians. While the main dishes usually feature a meat such as turtle, deer, snake or squab -- the day I ate there the special was racoon -- there's always a vegetarian alternative for that ingredient. For example, "Gone with the Wind," a dish good for one's mind, can be gotten with bean curd instead of brains, although presumably the latter is more effective.

Reasonably priced plates under "Vegetarian" are as delicately seasoned, good-looking and tasty as any vegetable dishes in the city, and certainly more intriguing with names such as Bright Buddha, Mushrooms & Moss and Lo Han Jiah. Thought effective in cleaning out the digestive system, the latter is a classic Buddhist combination of mushrooms, lily buds, gingko nuts, wheat gluten, snow peas, rice noodles and a kind of wispy black sea moss called "hair vegetable."

For 75 cents, under "Side Order," one can sample nutty-flavored black glutinous rice, believed to keep the hair from turning gray and the blood a deep red. Slightly more expensive are seaweed soup, rice porridge (nine kinds), and plates of quail, turtle, white tree fungus in syrup, or Chinese boxthorn with sea cucumbers.

The beverages are hardly run-of-the-mill. Ancient tonic wines such as Tiger Bone and Deer Tail are available as well as Gingseng Tea, Herbal Drink Dragon Brew and Soy Bean Juice. Perhaps taking a cue from less health-conscious American restaurants, you can also have a cup of coffee or a Tsingtao beer.