To treat the early stages of the common cold, take 50 gr. of garlic, the white heads of green onion, and fresh ginger, and boil in water; drink hot and cover yourself with a blanket so that you transpire.
When fever and chills are present, grate 30 gr. of ginger, boil it in water, add one teaspoon of brown sugar. To suppress coughing due to the common cold, grate 50 gr. of ginger and mix with 2 teaspoons of maltose, boil in 3 cups of water until the water is reduced to half a cup, and then sip slowly.
Reference: Chinese Foods for Longevity by Henry C. Lu p. 22-23
There is a whole book written on the wonders of ginger, garlic and green onion based on Traditional Chinse Medical (TCM) Food Therapy claiming to cure all most any kind of imaginable disease in man. The book includes more than twenty different recipes to cure the common cold with ginger, garlic and green onion!
Reference: Curing Diseases the Chinese Way: With Ginger, Garlic and Green Onion compiled by Wang Fuchun and Duan Yuhua