(Turnera diffusa)  Damiana has been hailed as an aphrodisiac since ancient times.  Other folk uses include asthma, bronchitis, neurosis, and various sexual disorders. It has also been promoted as a euphoria-inducing substance at various times.  Damiana may be a potentially useful herb for some female health problems.  It is known as a strengthening tonic for the nervous and hormonal systems.  An alkaloid in Damiana acts like the male hormone testosterone.  Increased levels of testosterone are associated with increased sex drive in both men and women.  Small amounts of this herb may relieve anxiety and create a general sense of well-being.

Most research has been done on the essential oil of damiana, which includes numerous small, fragrant substances called terpenes. However, it still is not known if the essential oil is the main active constituent of damiana. The leaves also contain the antimicrobial substances arbutin, alkaloids, and other potentially active compounds. 

The leaves of damiana were originally used as medicine by the indigenous cultures of Central America, particularly Mexico. Today the plant is found in hot, humid climates, including parts of Texas. 

To make a tea, add 1 cup boiling water to 1 gram of dried leaves, steep ten to fifteen minutes. Drink three cups per day. Tincture, take 2–3 ml three times per day. Tablets or capsules, 400–800 mg three times per day.

Precautions:  The leaves have a minor laxative effect, which is more pronounced at higher intakes, and may cause loosening of stools.  Excessive use of Damiana may result in over-stimulation.