Within what time window should alteplase be administered for suspected acute ischemic stroke?

Within what time window should alteplase be administered for suspected acute ischemic stroke?

• A. 3 hours
• B. 4.5 hours
• C. 6 hours
• D. 12 hours

Answer: (B)

Time to treatment is critical. The approved window for giving IV alteplase in suspected acute ischemic stroke is within 4.5 hours of symptom onset for patients who meet the criteria and have no contraindications. This extended window reflects evidence from trials like ECASS III that showed benefit in the 3–4.5 hour period with acceptable safety in selected patients. The earlier 3-hour window exists, but the question asks for the general recommended timeframe, which is up to 4.5 hours. Outside of this window (6 hours or 12 hours) IV alteplase is not routinely recommended. Always confirm there is no hemorrhage on imaging and assess contraindications before administration.

Time to treatment is critical. The approved window for giving IV alteplase in suspected acute ischemic stroke is within 4.5 hours of symptom onset for patients who meet the criteria and have no contraindications. This extended window reflects evidence from trials like ECASS III that showed benefit in the 3–4.5 hour period with acceptable safety in selected patients. The earlier 3-hour window exists, but the question asks for the general recommended timeframe, which is up to 4.5 hours. Outside of this window (6 hours or 12 hours) IV alteplase is not routinely recommended. Always confirm there is no hemorrhage on imaging and assess contraindications before administration.