Betamethasone phosphate is a prodrug that is rapidly metabolized to betamethasone. It is used to treat many inflammatory conditions like allergic states, dermatologic diseases, hematologic disorders, renal diseases, respiratory diseases, rheumatic disorders, and endocrine disorders. This drug is indicated when oral therapy is not feasible, it is an injectable suspension usually used intramuscularly, intralesionally, or by the intra-articular route. As betamethasone is a glucocorticoid, its mechanism of action is that of the glucocorticoid response element (GRE) of influencing COX-2/prostaglandin G/H synthase 2 suppression and lipocortin/annexin induction. By binding to the glucocorticoid receptor, it influences transcription factors AP-1 and NF-kB to block the transcription of COX-2/prostaglandin G/H synthase 2 which reduces the amount of prostanoids being produced from arachidonic acid. Prostanoids such as PGI2 and thromboxane A2 influence the effects of inflammation through vasoconstriction/dilation, pain sensitivity, and platelet aggregation. Betamethasone also affects the promoter of annexin-1, an important inflammatory protein as it affects leukocytes and blocks phospholipase A2 which reduces the amount of arachidonic acid being cleaved from the phospholipid bilayer. Reducing the amount of arachidonic acid formed further decreases the concentrations of prostanoids mentioned calming inflammation.

Betamethasone phosphate Pathway References