Hydroxychloroquine Retinopathy

Overview

Hydroxychloroquine is a medication used to treat autoimmune conditions such as lupus and rheumatoid arthritis, and it has also been used for malaria. It is effective and generally well tolerated, but with long-term use it can, in some people, damage the retina, the light-sensing layer at the back of the eye. This complication is called hydroxychloroquine retinopathy.

The damage typically affects the macula, the central part of the retina responsible for sharp, detailed vision. Early on it usually causes no symptoms, but if it progresses it can lead to permanent loss of central vision. Because the change is often irreversible once it occurs, the focus is on prevention and early detection through regular eye screening, so the medication can be reviewed before significant damage develops. For most people the benefits of hydroxychloroquine outweigh this risk when proper dosing and monitoring are followed.

Symptoms

Early hydroxychloroquine retinopathy usually causes no symptoms, which is why screening is essential. As damage advances, symptoms may include:

• Difficulty reading or seeing fine detail
• Blurred or hazy central vision
• Missing patches or blind spots near the center of vision
• Trouble seeing in dim light
• Changes in color vision

Because noticeable symptoms usually mean damage has already occurred, regular eye monitoring aims to catch the earliest changes before vision is affected. Any new central vision change while taking the medication should be reported promptly.

Causes

The condition is caused by the toxic effect of hydroxychloroquine on retinal cells over time:

• Cumulative exposure: Risk rises with the total amount of drug taken over years.
• Daily dose relative to body weight: Higher doses for a person's size increase risk.
• Reduced drug clearance: Kidney disease can raise drug levels and risk.

The exact way hydroxychloroquine damages the retina is not fully understood, but it gradually harms the retinal cells of the macula.

Risk Factors

• Long duration of use (risk rises notably after several years)
• Higher daily dose relative to body weight
• Kidney disease, which slows drug clearance
• Use of certain other medications, such as tamoxifen
• Pre-existing retinal or macular disease
• Older age

Diagnosis

Detection relies on a baseline eye exam and ongoing screening using sensitive tests:

• Baseline exam: A dilated eye exam recommended around the time the medication is started.
• Optical coherence tomography (OCT): Detailed retinal scans that can show early thinning or damage.
• Visual field testing: Detects subtle blind spots near the center before vision is affected.
• Other tests: Such as fundus autofluorescence or a multifocal electroretinogram, used to find early toxicity.

Screening guidelines generally recommend a baseline exam and periodic monitoring, with more frequent checks for those at higher risk.

Treatment

The key action is recognizing toxicity early and reviewing the medication with the prescribing doctor.

• Reviewing the medication: If retinopathy is detected, the prescriber may stop or change hydroxychloroquine; this decision balances the benefit for the underlying disease against the risk to vision and is never made without medical guidance.
• Continued monitoring: Because damage can progress even after stopping the drug, ongoing eye follow-up is important.
• Low-vision support: Aids and rehabilitation if central vision is affected.

There is generally no way to reverse established damage, so prevention through correct dosing and screening is the priority.

Prevention

• Take hydroxychloroquine at the dose prescribed for your body weight and do not exceed it
• Have a baseline eye exam when starting the medication
• Attend regular eye screening as recommended, especially after several years of use
• Tell your eye doctor about kidney problems and all other medicines you take
• Report any change in central vision promptly
• Do not stop the medication on your own without medical advice

When to See a Doctor

If you take hydroxychloroquine, keep your scheduled eye screening appointments even if your vision seems fine. Contact your eye doctor promptly if you notice:

• Trouble reading or seeing fine detail
• Blurred central vision
• Blind spots or missing patches near the center of vision
• Changes in color vision

Discuss any concerns with the doctor who prescribes the medication rather than stopping it on your own, so the benefits and risks can be weighed together.

Related Topics

Frequently Asked Questions

References

1. American Academy of Ophthalmology. Recommendations on screening for chloroquine and hydroxychloroquine retinopathy.
2. MedlinePlus, U.S. National Library of Medicine. Hydroxychloroquine.
3. National Eye Institute (NEI). Retinal diseases.
4. American College of Rheumatology. Hydroxychloroquine (Plaquenil).