Coleus is a not a particularly remarkable plant to look at, yet it has a 3000-year history in Ayurvedic medicine and is mentioned in ancient Sanskrit texts as a tonic for a healthy heart and lungs.
Today, coleus is not just a herb for cardiovascular ailments but is increasingly used to assist weight loss by breaking down adipose tissue and preventing production of further fatty tissue.
In addition, coleus mildly stimulates the metabolism by increasing thyroid hormones and increases the secretion of insulin.
These therapeutic indications for coleus are due to its principal active compound, a diterpenoid called forskolin. This is the only plant-derived compound known to directly stimulate the enzyme, adenylate cyclase, and in turn, stimulates cellular cyclic AMP which boosts our metabolism.
Coleus forskohlii preparations used as eye drops are known to reduce eye pressure in glaucoma.
Like all good tonics, coleus directly stimulates digestion and is thought to assist in the absorption of nutrients in the small intestine.
Increased cellular cyclic AMP reduces histamine, making coleus beneficial in the treatment of allergies. Coleus is also a bronchodilator with an antihistamine action, making it useful in treating asthma.
It is a popular herb for angina and for the health of the heart.
Coleus increases stroke volume, which is the amount of blood pumped with each heartbeat and reduces the risk of blood clots. In addition, the herb lowers high blood pressure by acting to relax the arterial walls.
Indian and Chinese studies in the last two years have isolated a number of diterpenoids in the stem and leaves of coleus forskohlii with a focus on the treatment of gastric cancer and preventing metastatic (secondary) cancers. These have been carried out on animal models with considerable success.