Prednisone vs Dexamethasone: what is the difference?

How they differ

Both are corticosteroids that suppress inflammation through the glucocorticoid receptor, and dexamethasone is several times the more potent per unit weight. Prednisone is inactive as swallowed and must be converted by the liver into prednisolone, which dexamethasone does not require. They also differ in mineralocorticoid effect: prednisone retains some, so it holds sodium and water more than dexamethasone, which has essentially none, and that is why dexamethasone is preferred where fluid retention is a problem. Dexamethasone lasts far longer, with a biological effect measured in a day and a half against prednisone's half day. Dexamethasone carries a fluorine that prednisone lacks, at 392.5 against 358.4.

Side by side

Structural similarity 0.39 of 1, computed as a Morgan fingerprint Tanimoto coefficient. It measures shape, not effect.

Common questions

What is the difference between Prednisone and Dexamethasone?

Both are corticosteroids that suppress inflammation through the glucocorticoid receptor, and dexamethasone is several times the more potent per unit weight. Prednisone is inactive as swallowed and must be converted by the liver into prednisolone, which dexamethasone does not require. They also differ in mineralocorticoid effect: prednisone retains some, so it holds sodium and water more than dexamethasone, which has essentially none, and that is why dexamethasone is preferred where fluid retention is a problem.

Is Prednisone bigger than Dexamethasone?

Dexamethasone is the heavier molecule, 392.5 g/mol against 358.4 g/mol for Prednisone. Prednisone is C21H26O5 and Dexamethasone is C22H29FO5.