10.02.3 Drugs that Modify the Actions of Eicosanoids

There are a number of ways that medicines are used to modify the actions of eicosanoids. Firstly, at the level of synthesis, the production of all the eicosanoids can be inhibited by inhibiting phospholipase A₂ with the glucocorticoids. Also, at the level of synthesis, the production of prostaglandins and thromboxanes, but not leukotrienes, can be inhibited by inhibiting COX. There are two forms of COX, and both forms are inhibited by non-selective COX inhibitors such as aspirin, paracetamol, ibuprofen, and piroxicam. COX-2 is selectively inhibited by celecoxib and diclofenac. Secondly, the actions of the eicosanoids can be modified at the levels of the receptors. Selective agonists are available for the EP receptors (misoprostol and dinoprostone), IP receptor (iloprost) and FP receptor (latanoprost). These medicines are now discussed systematically.