1.(1) A history of allergic diseases and asthma; (2) Oral surgery and other operations prone to bleeding; (3) those who have taken enough anticoagulants orally;

　　Precautions for taking heparin sodium:

　　1.(1) A history of allergic diseases and asthma; (2) Oral surgery and other operations prone to bleeding; (3) those who have taken enough anticoagulants orally; (4) Excessive menstrual flow; (5) In pregnant and postpartum women (hepatocirrhosis increases the risk of maternal bleeding at 3 months after pregnancy or postpartum).

　　2. Effects of drugs on the elderly: Elderly people over 60 years old (especially elderly women) are more sensitive to heparin and prone to bleeding during medication, so dosage should be reduced and follow-up should be strengthened.

　　3. Effects of drugs on test value or diagnosis :(1) heparin can prolong the prothrombin time and prothrombin time, increase the experimental retention of sulfbrobrophthalein sodium (BSP) and result in false positive reaction, resulting in increased concentrations of T3 and T4, thus inhibiting the release of thyroid-stimulating hormone; (2) When heparin dose reaches 15000 ~ 20000U, serum cholesterol concentration decreases.

　　4. The coagulation time of whole blood should be measured before treatment (test tube method), and the prothrombin time and prothrombin time should be measured by one-stage method; During the treatment, complete blood coagulation time (test tube method), blood cell volume, stool occult blood test, urine occult blood test and platelet count should be measured.

　　5. In clinical practice, heparin dosage was adjusted according to APTT. The coagulation time should be maintained at 2 ~ 3 times before treatment, and THE APTT should be 1.5 ~ 2.5 times before treatment. The heparin dosage and the interval time of administration should be adjusted at any time. At the time of treatment, the above observations should be investigated before each medication, and measured several times a day in the future, and once a day at the maintenance dosage; The elderly, hypertension and liver and kidney insufficiency, because of their sensitivity to heparin response, need to pay more attention to monitoring.

　　6. In the case of long-term anticoagulant treatment, oral anticoagulation with diccoumarin can be added while heparin is used, and heparin should be discontinued after 36 ~ 48h, and then oral anticoagulant should be used alone to maintain anticoagulation.

　　7. If heparin is not effective orally, intravenous injection, intravenous drip and deep subcutaneous injection can be used. Intramural injection is generally not recommended, as it can lead to hematoma at the injection site; Subcutaneous injection should go deep into the fat layer (such as iliac crest and abdominal adipose tissue), the injection site needs to be constantly replaced, do not move the needle when the injection, the injection site should not be rubbed, but local oppression.

　　8. Intramuscular injection of other drugs should be prevented during administration.