When an overdose of low molecular heparin calcium is injected, the first thing that needs to be observed is the patient’s specific situation, monitoring the patient’s vital signs, testing the patient’s blood, platelets, and coagulation function, as well as liver and kidney function. Because of the wide variation in individual sensitivity to low molecular heparin calcium, some patients do not experience significant adverse effects when an overdose is injected. If the overdose is a small amount of injection, there is no need to be overly nervous. However, if the patient develops a tendency to bleed, if the bleeding is only mild, it is only necessary to reduce the amount of the drug as well as delay the administration of the drug. If the situation is more serious, it is necessary to consider the application of fisetin sulfate to neutralize the excess of low molecular heparin calcium. Generally speaking, 0.6mL of fisetin sulfate is able to neutralize about 950iu of low molecular heparin calcium. However, the time it takes for the body to metabolize heparin after injection should be taken into account, so reduce the amount of fisetin as appropriate.