What is the typical maximum single-dose aspirin in EMS?

• A. 325 mg per dose (protocols may allow up to 325 mg).
• B. 81 mg per dose.
• C. 500 mg per dose.
• D. 1000 mg per dose.

Answer: (A)

In EMS, the goal is rapid, reliable platelet inhibition to help limit clot growth during a suspected heart attack while keeping bleeding risk low. Aspirin works by irreversibly inhibiting COX-1 in platelets, which lowers thromboxane A2 and reduces platelet aggregation for the life of the platelets. A single standard-strength, chewable tablet is used because it provides a quick, effective amount that’s practical to administer in the field. A dose smaller than this standard amount wouldn’t achieve optimal antiplatelet effect in the critical early minutes, while a larger dose wouldn’t add benefit and would raise the risk of stomach irritation and bleeding. So, one standard-strength tablet per dose is the typical maximum in EMS protocols.