The Anticancer and Heat-Clearing, Dampness-Draining Actions of Baiying (Solanum lyratum)

Baiying is a plant of the Solanum genus in the nightshade family. Baimao teng ("white-vine") is the whole herb of Baiying; because the stems and leaves of Baiying are covered with a layer of white hairs, its whole herb is used medicinally under the name baimao teng. Traditional TCM holds that baimao teng is sweet and bitter in taste, cold in nature, and slightly toxic, entering the liver, gallbladder, and kidney meridians. It clears heat and drains dampness, resolves toxicity and reduces swelling. It is used mainly for damp-heat jaundice, cholecystitis, gallstones, nephritic edema, rheumatic joint pain, female damp-heat vaginal discharge, infantile high fever and convulsion, welling abscesses and scrofula, eczema with itching, and shingles. The usual internal dose of the dried herb as a decoction is 15–30g; of the fresh herb, 30–60g. It may also be decocted for external washing or the fresh herb crushed for poultice. However, baimao teng is slightly toxic; overdose causes throat burning, nausea, vomiting, dizziness, and dilated pupils.

Baiying has a long medicinal history. In the Divine Farmer's Materia Medica (Shennong Bencao Jing), Baiying was listed as a top-grade herb. The Divine Farmer's Materia Medica held that Baiying "mainly treats cold and heat and the eight types of jaundice, quenches thirst, supplements the center and boosts qi; long-term use lightens the body and prolongs life." Thus the Divine Farmer's Materia Medica's understanding of Baiying was incomplete—it did not recognize its toxicity.

The "cold and heat, eight jaundices" here refer to jaundice. Baimao teng has special efficacy for jaundice caused by infectious hepatitis, cholecystitis, and gallstones. It is reported that taking 60–120g of baimao teng decocted daily for jaundice due to infectious hepatitis treated 36 patients; after four days of medication, loss of appetite, general fatigue, hepatosplenomegaly, and liver-area pain all improved one after another, returning to normal within 1–2 weeks. Except for one case that failed, the remaining 35 all fully recovered.

Folk medicine in Fujian has a folk remedy for cholecystitis: baimao teng 60g, Gardenia 24g, and Money grass (Jinqiancao) 30g, decocted in water. This formula heavily uses baimao teng, together with Gardenia and Money grass, which likewise clear heat, drain dampness, and reduce jaundice—precisely the key to resolving cholecystitis.

Baimao teng also has antitumor effects. Its hot-water extract (4kg extract from 60kg of dried herb) is antitumor. In vitro, the components SL-c and SL-d in the extract markedly inhibit the human cervical cancer JTC-26 cell line. Baimao teng also works well for lung cancer and vocal-cord cancer.

The Hubei Chinese Herbal Flora records that baimao teng "clears heat and resolves toxicity, promotes urination and reduces swelling, and fights cancer and stops pain," and may be used for "colds with fever, jaundice hepatitis, dysentery, nephritic edema, cholecystitis, gallstones, lymph node tuberculosis, esophageal cancer, intestinal cancer, cervical cancer, cervical erosion, vaginal discharge, boils and swellings, shingles, and eczema."

Fresh baimao teng stems and leaves crushed and squeezed for juice, dropped into the ear, also treat purulent ear (otitis media). It is reported that after first washing away purulent debris from the ear with saline and drying it with a cotton swab, baimao teng juice is dropped in; the head is tilted toward the unaffected side for a moment and the tragus gently pressed, 2–3 times daily. Of 21 cases treated, 16 had all symptoms disappear after one week with hearing restored, 3 recovered after two weeks, and 2 failed.