**Question:** Dose of streptokinase to be used in MI is

A. 500,000 IU
B. 1,000,000 IU
C. 3,000,000 IU
D. 5,000,000 IU

**Correct Answer:** .

**Core Concept:** Streptokinase is a fibrinolytic agent used for thrombolysis in acute myocardial infarction (MI). Thrombolysis is the process of breaking down blood clots, and streptokinase is a type of thrombolytic enzyme that works by dissolving fibrin, a key component of blood clots.

**Why the Correct Answer is Right:** Streptokinase is used to dissolve blood clots in acute myocardial infarction (MI), which is a life-threatening complication of coronary artery disease. The correct dose depends on the patient's weight and other clinical factors, but the recommended dose for adults is typically around 1,000,000 IU (International Units). This dose is based on the findings from clinical trials that have established the safety and efficacy of this dose. Large clots or those in patients with low cardiac output may require a higher dose.

**Why Each Wrong Option is Incorrect:**

A. The dose of 500,000 IU is too low, and thrombolysis may not be effective in dissolving the clot in a large or long-standing clot.

B. The dose of 1,000,000 IU is the recommended dose for adults, as mentioned above, but this option repeats the correct answer.

C. The dose of 3,000,000 IU is too high and carries an increased risk of bleeding complications due to increased enzymatic activity.

D. The dose of 5,000,000 IU is extremely high and may cause significant bleeding complications due to increased enzymatic activity.

**Clinical Pearl:** The selection of the correct streptokinase dose requires a thorough evaluation of the patient's clinical condition, including the size and duration of the clot, as well as the patient's weight and coagulation status. A tailored approach ensures optimal thrombolysis while minimizing the risk of bleeding complications.