Abstract: A medicinal substance for increasing fertility in mammalian males and for use as an anti-microbial or anti-inflammatory agent by mammals produced by boiling radish leaves, radish stems or portions thereof in water for a period of time sufficient to produce a tea containing an extract from the radish leaves and stems or portions thereof. Alternatively, the radish leaves and stems may be placed in hot water for a period of time sufficient to produce a tea containing the extract. The resulting tea can be drunk hot or cold and may be stored in a refrigerator for extended periods of time for later use. Patients taking a daily dosage of this tea have shown greatly improved sperm density and improved motility and morphology after use for several weeks. Dosages of this tea are also effective in treating prostatitis. The preferred radish plant is the spring radish of the species Raphanus sativus. The leaves of other radish plants including wild and winter or oriental radishes may also be used.