OTC is also a quasi-Chinese medicine, including OTC drugs and prescription drugs. Prescription drugs refer to drugs that can only be purchased and used with the prescription of licensed doctors or licensed assistant doctors. OTC is an over-the-counter drug, which refers to the drug that can be judged, purchased and used by itself without the prescription of a licensed physician or a licensed assistant physician. Non-prescription drugs are selected according to the principle of "safe application, exact curative effect, stable quality and convenient use".