A 32-year-old woman with chronic cutaneous lupus is started on hydroxychloroquine. To minimise the risk of retinopathy, the daily dose should not exceed:

• A 3 mg/kg of ideal body weight
• B 5 mg/kg of actual body weight ✓
• C 6.5 mg/kg of ideal body weight
• D 10 mg/kg of actual body weight

Explanation

Current ophthalmology guidance caps hydroxychloroquine at 5 mg/kg of actual body weight per day, because retinopathy risk rises sharply above this threshold and is cumulative with duration of therapy. The older ceiling of 6.5 mg/kg based on ideal body weight allowed toxic doses in obese patients. Baseline and annual eye examination are advised after five years of therapy.

Reference: Rook's Textbook of Dermatology, 9th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.