Myrrh is an extract of a tree gum resin that has long been used as a fragrance and as an herbal medicine. Animal studies suggest it may reduce inflammation and fevers or protect against substances that are hard on the digestive system. It may also have antioxidant properties and stimulate the thyroid gland. Other experiments suggest it may slow cancer growth in mice or isolated cancer cells, but it is unknown if such effects can occur in humans.
Only a few small studies have been conducted in humans, some of which were herbal preparations that included other compounds. Additional studies are needed to determine what utility myrrh may have for various conditions.