Myrrh gum is a resin secreted by several trees of the Commiphora genus. Native to Africa, Arabia and India, these trees have a long history of cultivation. The bark of the tree is scored and the resin, or gum, is collected when it coagulates on the surface. Myrrh gum has a yellow cast and ranges from clear to cloudy, darkening with age. The resin is widely used in traditional medicine and is a prized ingredient in incense.
The species Commiphora myrrha is the most common provider of myrrh gum. This shrub-like tree is native to the desert regions of the Eastern Mediterranean and Arabian Peninsula. Seldom reaching more than 9 feet (2.74 m) in height, the plant has a tough, grayish bark, sharp spines and an ovate leaf.
To collect the myrrh gum, incisions are made through the bark into the living wood of the tree. A milky liquid, the resin slowly oozes out and dries on exposure to air to form several yellowish droplets. These droplets, or tears, are collected from cultivated trees at intervals that vary according to local conditions. Typically, the tapping process is repeated twice a month for a harvesting season that lasts four to six months. After a drying period of up to three months, the myrrh is ready for shipment.
Traditional systems of medicine have made use of myrrh gum for many centuries. Ayurveda, traditional Indian medicine, finds myrrh to have beneficial effects on the circulatory and nervous systems. In traditional Chinese medicine, myrrh gum plays a prominent role in the treatment of circulatory problems, inflammation and arthritis. Myrrh can also be found in modern pharmaceuticals with applications ranging from the treatment of gum disease to use as an antifungal for athlete's foot.
Certain side effects of myrrh gum have been recognized in traditional and modern use. Irritation of the eyes and mucous membranes has been associated with myrrh use in some instances. It is often recommended that pregnant and nursing women as well as young children not be exposed to products containing the resin.
Myrrh has played a prominent role in worship in some cultures, as well. In ancient Egypt, myrrh was used in the embalming stage of mummification. It was an ingredient in the ritual incense of the Hebrew Tabernacle and the devotional incense used throughout the Indian subcontinent. Roman Catholic and Eastern Orthodox liturgy continues to make use of myrrh in worship and sacramental rites.