About Betamethasone Potent glucocorticoid, Anti-inflammatory, immunosuppressent. Mechanism of Action of Betamethasone The drug exerts it`s pharmacological action by penetrating and binding to cytoplasmic receptor protein and causes a structural change in steroid receptor complex. This structural change allows it`s migration in to the nucleus and then binding to specific sites on the DNA which leads to transcription of specific m-RNA and which ultimately regulates protein synthesis. It exerts highly selective glucocorticoid action. It stimulates the enzymes needed to decrease the inflammatory response.