What is the primary action of ibuprofen in the body?

Ibuprofen primarily acts by inhibiting the synthesis of prostaglandins in the body. Prostaglandins are lipid compounds that have several important roles, including mediating inflammation, pain, and fever. When tissues are damaged or inflamed, the body increases the production of prostaglandins, which contribute to pain and swelling.

By blocking the enzymes involved in prostaglandin synthesis, specifically cyclooxygenase (COX-1 and COX-2), ibuprofen reduces the levels of these inflammatory mediators. This leads to decreased inflammation, alleviation of pain, and reduction of fever. The effectiveness of ibuprofen as an anti-inflammatory, analgesic, and antipyretic agent is largely attributed to this primary mechanism of action.

Other options relate to different mechanisms that are not the main action of ibuprofen. For instance, inhibiting leukotriene synthesis is a different pathway that some other medications target, and is not the primary action of ibuprofen. Additionally, promoting blood flow to tissues or stimulating nerve endings does not align with ibuprofen's pharmacological activity, as its role is primarily about reducing pain and inflammation rather than increasing blood flow or nerve stimulation.