What is the recommended dosage of Hydroxychloroquine (Plaquenil) for patients with retinal disease?

From the Guidelines

Hydroxychloroquine dosing should be kept at or below 5 mg/kg of actual body weight per day to minimize the risk of retinal toxicity. For most adults, this translates to a maximum of 400 mg daily 1. Patients should undergo a baseline ophthalmologic examination before starting treatment or within the first year, followed by annual screening after 5 years of continuous use (or sooner in patients with risk factors) 1. Risk factors that warrant earlier or more frequent screening include kidney disease, liver disease, use of tamoxifen, macular disease, and age over 60 years. The risk of retinopathy increases significantly with higher doses and longer duration of use, particularly beyond 5 years 1. Hydroxychloroquine-induced retinopathy is typically irreversible, which is why proper dosing and regular monitoring are essential. The medication concentrates in melanin-containing tissues including the retina, and over time can damage photoreceptors and retinal pigment epithelium, potentially leading to permanent vision loss if not detected early. Patients should be advised to report any visual changes promptly, including difficulty reading, decreased color vision, or central vision disturbances.

Key Considerations

• The daily dosage of hydroxychloroquine should not exceed 5 mg/kg of actual body weight to keep the risk of retinal toxicity below 2% for up to 10 years of use 1.
• Baseline testing is crucial to rule out pre-existing retinal conditions, and annual screening should start no more than 5 years after treatment initiation 1.
• Effective communication among healthcare providers, patients, and eye care specialists is vital to optimize the safety and utility of hydroxychloroquine therapy 1.
• Patients with risk factors such as kidney disease, liver disease, or age over 60 years may require more frequent screening 1.

Monitoring and Patient Education

• Patients should be educated on the importance of reporting any visual changes promptly, including difficulty reading, decreased color vision, or central vision disturbances.
• Regular monitoring and adherence to the recommended dosage are critical to preventing hydroxychloroquine-induced retinopathy and preserving visual function.

From the FDA Drug Label

Daily doses exceeding 5 mg/kg (actual weight) of hydroxychloroquine sulfate increase the incidence of retinopathy [see Warnings and Precautions (5.2)].

• The recommended dosage for hydroxychloroquine to minimize the risk of retina disease is to not exceed 5 mg/kg of actual body weight per day.
• Risk factors for retinal damage include:
  • Daily hydroxychloroquine sulfate dosages ≥ 5 mg/kg of actual body weight
  • Durations of use greater than five years
  • Renal impairment
  • Use of concomitant drug products such as tamoxifen citrate
  • Concurrent macular disease
• Patients should have a baseline ocular examination within the first year of starting hydroxychloroquine sulfate, and annual examinations if they are at higher risk of retinal damage 2.

From the Research

Hydroxychloroquine Dosage Guidelines for Retina Disease

• The risk of hydroxychloroquine retinopathy is more common than previously recognized, especially at high dosages and long duration of use 3.
• Daily consumption of 5.0 mg/kg of real body weight or less is associated with a low risk for up to 10 years 3.
• The overall prevalence of hydroxychloroquine retinopathy was 7.5%, but varied with daily consumption and duration of use 3.
• Other major risk factors include kidney disease and concurrent tamoxifen citrate therapy 3.

Risk Factors for Hydroxychloroquine Retinopathy

• Duration of therapy and cumulative dose are proposed risk factors, but there are many exceptions 4.
• Commonly accepted risk factors include receiving >6.5 mg/kg/day or a cumulative dose of >1000 g of HCQ, being on treatment for >5 years, having renal or liver dysfunction, having pre-existing retinopathy, and being elderly 4.
• Asian patients with HCQ retinopathy may demonstrate an extramacular or pericentral pattern of disease 5.

Screening and Monitoring for Hydroxychloroquine Retinopathy

• Novel technologies such as optical coherence tomography (OCT), fundus autofluorescence (FAF), and multifocal electroretinogram (mfERG) may provide the earliest structural and functional evidence of toxicity 4.
• Central visual field testing (10-2 visual fields) is a well-established technique for screening 4.
• Screening for HCQ retinopathy remains an area of considerable debate, including issues of when, who, and how to screen 4.