A patient maintained on prednisolone 40 mg daily needs conversion to an equivalent anti-inflammatory dose of hydrocortisone. The appropriate hydrocortisone dose is:
- A 40 mg
- B 80 mg
- C 160 mg ✓
- D 320 mg
Correct answer: C. 160 mg
Explanation
The standard equivalence is 20 mg hydrocortisone = 5 mg prednisolone, a ratio of 4:1 by weight. Therefore 40 mg of prednisolone corresponds to 160 mg of hydrocortisone. Hydrocortisone also carries significant mineralocorticoid activity, whereas prednisolone has minimal such effect, so replacement decisions must account for this difference. Choosing 80 mg applies the wrong ratio, and 320 mg would represent an eightfold error leading to overtreatment and Cushingoid effects.
Reference: Katzung Basic and Clinical Pharmacology, 15th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.