Do you understand the mineralocorticoid and glucocorticoid effects of corticosteroids? I bet many of you do not…
I am going to keep this brief and simple as you can look up more advanced pharmacological topics on Google.
Mineralocorticoid activity = think “mineral” and “sodium.” Increased mineralocorticoid activity will cause excessive sodium retention, which will then cause increased fluid retention. This is one of the reasons why some people “swell up” on prednisone.
Glucocorticoid activity = think “glucose.” Increased glucocorticoid activity increases gluconeogenesis in the liver and decreased peripheral glucose uptake, which will lead to hyperglycemia. This is why you need to be cautious when giving corticosteroids to diabetics!
Prednisone has high mineralocorticoid activity whereas dexamethasone has minimal mineralocorticoid activity. Therefore, dexamethasone would be the better choice in someone who has uncontrolled hypertension as it will not cause fluid retention like prednisone.
On the other side of the coin, prednisone has lower glucocorticoid activity compared to dexamethasone, therefore would be the safer option in the diabetic.
The link below is a nifty chart describing the mineralocorticoid and glucocorticoid effects of corticosteroids. Memorize this and become more proficient with prescribing steroids!