The medicinal properties of chives are as varied as their uses in the kitchen. Chives are known to stimulate the appetite and promote good digestion. They can be used to help ease stomach upset, clear a stuffy nose, reduce flatulence and prevent bad breath. Combined with a low-salt diet, some believe they help promote healthy blood pressure. Plus, they have a mild diiuretic effect, as well as some antibacterial properties.
(Source: The Complete Guide to Natural Healing)