What side effect is commonly associated with fludrocortisone therapy for orthostatic hypotension?

• A. Increased serum potassium
• B. Decreased serum calcium
• C. Decreased serum potassium
• D. Increased glucose levels

Answer: (C)

Fludrocortisone is a synthetic corticosteroid that has substantial mineralocorticoid activity, leading to increased sodium reabsorption in the kidneys. This sodium retention is accompanied by water retention, which helps to increase blood volume and blood pressure, making it useful in treating conditions such as orthostatic hypotension.

A notable side effect of fludrocortisone therapy is a decrease in serum potassium levels. The increased renal retention of sodium is coupled with increased excretion of potassium, which can lead to hypokalemia (low potassium levels). This is a significant consideration in managing patients on fludrocortisone, especially because electrolyte imbalances can have serious clinical consequences.

Other side effects, like increased glucose levels, while relevant in corticosteroid therapy, are not the direct side effect commonly associated with fludrocortisone in the context of treating orthostatic hypotension specifically. Therefore, decreased serum potassium is the most recognizable side effect linked to the administration of fludrocortisone in this therapeutic scenario.