Cang Erzi foot soak once put how much is not clearly defined, foot soak as daily life behavior, generally not considered to have a therapeutic effect on the disease, Cang Erzi has the efficacy of expelling wind and dampness, the specific use of the need to comply with medical advice. CangErZi decoction soup internal dose pharmacopeia recommended for 3 ~ 10g, external use appropriate amount, no clear specific dose. Cang Er Zi is toxic, the use of too large a dose can cause poisoning, manifested as depression, general weakness, loss of appetite, nausea, vomiting, abdominal pain, diarrhea, dizziness, drowsiness, and even coma, shock and other adverse reactions. External foot soak should be used under the guidance of a doctor. Cynanchum has the effect of clearing nasal orifices, dispersing wind-cold and dispelling wind-dampness. It is used for wind-cold headache, nasal congestion and runny nose, nasal abyss (sinusitis), congested nose (allergic rhinitis), rubella itching, dampness paralysis and contracture (rheumatism paralysis, limb spasm). This product is easy to dissipate gas and blood consumption, people with a weak constitution should not take Cang Er Zi, the specific use of drugs need to be rationally applied under the guidance of a physician.