Ibuprofen is a nonsteroidal anti-inflammatory drug NSAID that is commonly used to alleviate pain, reduce inflammation, and lower fever. At the molecular level, it works by inhibiting the activity of enzymes called cyclooxygenases COX , specifically COX-1 and COX-2. These enzymes play a crucial role in the synthesis of prostaglandins, which are lipid compounds that have various physiological effects, including promoting inflammation, pain, and fever.Prostaglandins are synthesized from arachidonic acid, a fatty acid that is released from cell membranes when cells are damaged or under stress. The COX enzymes convert arachidonic acid into prostaglandin H2 PGH2 , which is then further converted into various types of prostaglandins and thromboxanes by specific enzymes. These prostaglandins and thromboxanes act as signaling molecules and are involved in various physiological processes, such as vasodilation, vasoconstriction, platelet aggregation, and modulation of pain and inflammation.Ibuprofen works by binding to the active site of the COX enzymes, thereby blocking their ability to convert arachidonic acid into PGH2. This inhibition of COX activity leads to a decrease in the production of prostaglandins and thromboxanes, which in turn reduces inflammation, pain, and fever.It is important to note that ibuprofen is a non-selective COX inhibitor, meaning it inhibits both COX-1 and COX-2 enzymes. COX-1 is involved in the production of prostaglandins that protect the stomach lining and maintain normal kidney function, while COX-2 is mainly involved in the production of prostaglandins that cause inflammation and pain. The non-selective inhibition of both COX enzymes by ibuprofen can lead to some side effects, such as gastrointestinal irritation and increased risk of bleeding, especially with long-term use or at high doses. However, the overall benefits of ibuprofen in alleviating pain and reducing inflammation generally outweigh these potential side effects for most people.