1. (1) patients with liver and renal insufficiency; (2) uncontrolled severe hypertension; (3) patients with a history of peptic ulcer.

　　2. Effects of drugs on pregnancy: dextroheparin sodium should not be used in the first 3 months of pregnancy.

　　3. Excessive heparin sodium can be used as antagonist protamine.

　　4. Dheparin sodium is not suitable for intramuscular injection. Platelet counts should be performed before medication.

　　5. For patients with severe bleeding, 1mg of protamine and 100U of protamine sulfate can be injected intravenously.