The three major complications of thrombolysis are bleeding, allergy, and reperfusion injury. The principle of thrombolytic therapy is to dissolve the blood clot and thus recanalize the blood vessel, so thrombolytic drugs can also reduce the coagulation function and cause cerebral bleeding, gastrointestinal bleeding and bleeding from other organs. Commonly used thrombolytic drugs include urokinase, streptokinase, alteplase, etc. These drugs have different ingredients and may contain small amounts of impurities, so patients with different constitutions may have chills, fever, asthma, rash and other allergic manifestations. Ischemia-reperfusion injury is also a common complication of thrombolysis, for example, if thrombolysis is performed after the infarction has been formed for a long time, such patients are more likely to have oxygen radical overload, which can aggravate the original disease and lead to hypotensive shock in severe cases, requiring timely resuscitation.