Herb of Spirodela polyrrhiza (L.) Schleid., family Lemnaceae.
An aquatic herb. Leaf-like stem flat-ovate, 1 or 2-5 blades clustered,
at the upper surface and purple red on the back,with 5-11 palmate veins,
and numerous slender roots. Acrid in taste, cold in nature, and attributive
to lung channel.
1. Induce sweating to expel the exogenous evils from the body surface
and let out the skin eruption: For common cold of wind-heat type with
fever and anhidrosis, the early stage of measles and other eruptive diseases
with incomplete eruption.
2. Promote diuresis to reduce edema: For superficial syndrome with edema
Containing postassium acetate and chloride which exert diuretic effect.
2. Oral administration of its decoction or infusion (2g/kg) can reduce
vaccine-induced fever in rabbits.
3. Cardiotonic on the heart of frog weakened by quinine. Also causing
constriction of blood vessels and rising of blood pressure.