Hydroxychloroquine Dosing for a 13-Year-Old Girl Weighing 52 kg
For a 13-year-old girl weighing 52 kg, hydroxychloroquine should be dosed at 260 mg daily (calculated as 5 mg/kg actual body weight), not to exceed 400 mg daily, to minimize retinal toxicity risk while maintaining therapeutic efficacy. 1
Dosing Calculation and Rationale
The American Academy of Ophthalmology recommends a maximum daily dose of 5.0 mg/kg based on actual body weight for hydroxychloroquine, which should not exceed 400 mg daily regardless of weight 1
For this patient: 52 kg × 5.0 mg/kg = 260 mg daily 1
This dose is well below the 400 mg maximum ceiling and represents the safest long-term dosing strategy 1
Why Actual Body Weight (Not Ideal Body Weight)
Real weight-based dosing is now recommended because hydroxychloroquine stores primarily in melanotic tissue, liver, and kidney—not in fat or muscle 1
Previous ideal body weight calculations resulted in systematic overdosing in thin individuals and underdosing in heavier patients 1
The American Academy of Ophthalmology guidelines shifted to actual body weight dosing to account for retinopathy risk evenly across different body types 1
Retinopathy Risk at Recommended Doses
Patients maintained at 5.0 mg/kg have <1% risk of retinopathy in the first 5 years and <2% risk up to 10 years of therapy 1
Risk increases sharply to approximately 20% after 20 years of continuous use, even at recommended doses 1
Daily doses exceeding 5 mg/kg significantly increase the incidence of retinopathy, which can be permanent and progress even after drug discontinuation 1, 2
A large contemporary cohort study found overall cumulative retinopathy incidence of 8.6% at 15 years, with most cases being mild when proper dosing was followed 3
Critical Monitoring Requirements
Baseline ophthalmologic examination is required before starting therapy 1
Annual screening should begin after 5 years of continuous use to detect toxicity at the earliest stage 1
Closer monitoring should be considered if cumulative dose exceeds 1000 g or if any retinopathy risk factors exist 1
No treatment exists for hydroxychloroquine retinopathy once it develops, making prevention through proper dosing and monitoring essential 1
Administration Instructions
Administer hydroxychloroquine orally with food or milk to improve gastrointestinal tolerability 2
Do not crush or divide the tablets 2
Available as 200 mg tablets, so this patient would receive one 200 mg tablet daily (slightly below the calculated 260 mg, but within safe parameters) 2