Professional and Linguistic Assessments Board (PLAB) Practice Exam

Which of the following drug categories is ranked higher in potency for mineralocorticoid activity than glucocorticoid activity?

1. Fludrocortisone and hydrocortisone

2. Dexamethasone and prednisolone

3. Hydrocortisone and prednisolone

4. Fludrocortisone and prednisolone

The correct answer is: Fludrocortisone and hydrocortisone

Fludrocortisone is a synthetic corticosteroid that has a significantly higher mineralocorticoid activity compared to its glucocorticoid effects. Its primary use is in conditions where sodium retention is desired, such as in adrenal insufficiency or orthostatic hypotension. Hydrocortisone, on the other hand, is generally known for its glucocorticoid activity but still possesses some mineralocorticoid effects, although less potent than those of fludrocortisone. The combination of fludrocortisone and hydrocortisone illustrates a scenario where the mineralocorticoid activity supersedes that of glucocorticoid activity to a notable extent, particularly because of fludrocortisone’s strong mineralocorticoid potency. This combination highlights a categorization of drugs where the mineralocorticoid function is prominent. In contrast, dexamethasone and prednisolone, both belonging mainly to glucocorticoids, do not possess mineralocorticoid activity at levels that would place them as rank higher in potency for that action. Hence, while they have glucocorticoid properties, they lack the significant mineralocorticoid effects characteristic of options including flud