This section is from the book "Botanic Drugs Their Materia Medica, Pharmacology and Therapeutics", by Thomas S. Blair. Also available from Amazon: Botanic Drugs, Their Materia Medica, Pharmacology and Therapeutics.
Turnera aphrodisiaca. A gentle stimulant not unlike ordinary tea, and used as such in Mexico. There is no creditable evidence that damiana possesses aphrodisiac properties. It is noted here simply to aid in dispelling a popular but unfounded belief. See the Pharmaceutical Review, Vol. 22, p. 126.