Clinically commonly used dog skin cream, rheumatism pain relief cream, Yunnan Baiyao cream, etc. is mostly 6-12 hours to change, and for the black ointment, due to the larger amount of medicine generally need to be applied for about 3-7 days. In the clinical specific use of plasters a few days for a change with a variety of factors, such as the type of plasters or plasters contained in the composition of the drug, half-life, plaster matrix, etc., the specific paste a few days for a change it is best to read the instructions in detail or consult a physician, pharmacist, and so on. Ointment is a commonly used external medicine, has a quick effect, good efficacy, few side effects, etc., with blood circulation, reduce blood stasis, swelling and pain, wind and dampness, etc., commonly used in the treatment of rheumatism and paralysis, lumbar muscle strain, lumbar disc prolapse and other diseases.