A number of herbs seem to influence sexual function and enhance sexual vitality, in addition to the many botanicals that have been used for treating various sexual maladies. Ginseng root is the classic example of a sexual strengthening herb. It is used more for men than for women, though when the lack of sexual energy is a result of fatigue, ginseng may help in both sexes. The aphrodisiac and sexual power capacities of ginseng, however, are only anecdotal and not supported by research; its main benefit may be its effects in supporting general vitality. Dong quai and Fo-ti tieng are two other herbal roots used in traditional Chinese medicine. Dong quai is a female herb that acts as a blood purifier, antispasmodic for cramps, and as a hormonal tonic. Fo-ti tieng, or Polygonium multiflore, is used more in males as a kidney tonic and diuretic, and to enhance fertility. It is also used for blood sugar programs. Both herbs can be taken in capsules or boiled to make tea. Damiana leaf has an historical reputation as an aphrodisiac and a stimulant of sexual activity. Good-quality (fresh, dried) damiana has helped many people stimulate their sexual appetites. Saw palmetto herb is best known for its treatment of male prostate problems. It and damiana have been used together to enhance sexual health. Both are also employed for respiratory difficulties. Licorice root seems to possess some estrogenic properties and has been used in many female tonifying formulas. It may be useful for reproductive health and for treating infertility. Sarsaparilla root contains "building block" chemicals that stimulate the synthesis of steroid sex hormones.