Muira Puama
Muira puama is a bush / small tree up to 5 meters in height and produces pungent flowers with a jasmine like fragrance.
Historically, Muira Puama has long been used in the Amazon by indigenous peoples for a number of purposes. In Brazilian herbal medicine, muira puama still is a highly-regarded sexual stimulant with a reputation as a powerful aphrodisiac. It has been in the Brazilian Pharmacopoeia since the 1950s.
Muira puama, also called “potency wood,” and is native to the Brazilian Amazon and other parts of the Amazon rainforest.
Muira Puama comes from the stems and roots of the Ptychopetalum olacoides plant, and is widely used in the Amazon region of South America as an aphrodisiac, tonic and cure for rheumatism and muscle paralysis.
A study, entitled "Male Sexual Asthenia," focused on sexual difficulties associated with asthenia, a deficiency state characterised by fatigue, loss of strength, or debility, all symptoms of a testosterone deficiency. The study population consisted of 100 men over 18 years of age who complained of impotence or loss of libido, or both. A total of 94 men completed the study and were evaluated. Muira puama treatment led to significantly increased frequency of intercourse for 66% of couples. Of the 46 men who complained of loss of desire, 70% reported intensification of libido. The stability of erection during intercourse was restored in 55% of patients and 66% of men reported a reduction in fatigue. Other beneficial effects included improvement in sleep and morning erections.
Treatment with muira puama was much more effective in cases with the least psychosomatic involvement. Of the 26 men diagnosed with common sexual asthenia without noticeable sign of psychosomatic disorder, the treatment was effective for asthenia in 100% of cases, the lack of libido in 85% of cases, and for inability of coital erection in 90% of cases.
The latter finding confirms that broad tonic action of muira puama on conditions of fatigue and stress related sexual dysfunction. Since muira puama is not an artificial stimulant, it fortifies the system over a period of time. Some men report increased vitality within two weeks, while the full effects build over several weeks.

Based on the clinical reports documenting the libido and energy enhancing effects of muira puama, it is possible that this herb induces these positive changes by favourably altering the hormone balance in aging men, i.e. increases free testosterone and/or suppresses excess estrogens.

Main Actions of Muira Puama:

• increases libido 
• is a male tonic: root, bark
• promotes sexual function
• relieves pain
• calms nerves
• reduces fatigue
• relieves depression
• lowers blood pressure
• enhances memory
• prevents ulcers
• protects brain cells