AEMCA Practice Exam

Aspirin works primarily by inhibiting the cyclooxygenase (COX) enzymes, which play a crucial role in the synthesis of prostaglandins. Prostaglandins are compounds that contribute to inflammation, pain, and fever. By blocking these enzymes, aspirin effectively reduces the production of prostaglandins, leading to a decrease in inflammation and alleviating pain. This mechanism is particularly important in conditions such as arthritis, where inflammation is a significant issue.

The other options do not describe aspirin's mechanism of action. For instance, serotonin-related actions pertain more to other medications, particularly those affecting mental health and mood. The dilation of blood vessels and reduction in heart rate relate to different classes of drugs used for cardiovascular conditions, not aspirin's primary functions. Thus, the correct role of aspirin centers on its inhibition of COX enzymes to provide its therapeutic effects.