Lemongrass is a plant in the grass family. There are over 100 lemongrass species, including Cymbopogon citratus, which is often used in foods and medicine.
Lemongrass leaf and essential oil contain chemicals that might help prevent some bacteria and yeast from growing. Lemongrass also contains chemicals that might relieve pain and swelling.
People use lemongrass for stomach pain, dandruff, high cholesterol, gingivitis, thrush, and many other conditions, but there is no good scientific evidence to support these uses.
Don't confuse lemongrass with other plants and ingredients that have similar names, including citronella oil, lemon eucalyptus, and citronella (stone root). These are not the same.