What are the early signs of hydroxychloroquine toxicity?
Asked by: scraper | Last update: July 21, 2026Score: 0/5 (0 votes)
In the early stages, hydroxychloroquine (Plaquenil) toxicity is typically asymptomatic. When early signs or subjective symptoms do manifest, they primarily involve the eyes and may include:
What are the symptoms of hydroxychloroquine toxicity?
If they do have symptoms, they complain of visual color deficits, specifically red objects; missing central vision; difficulty reading; reduced or blurred vision; glare; flashing lights; and metamorphopsia. The symptoms are often in both eyes. In keratopathy, patients complain of halos around light and photophobia.
Can Plaquenil toxicity be reversed?
Plaquenil Toxicity: Definition and Importance
Even when detected, vision loss cannot be reversed, making early detection and regular screening crucial.
How long does hydroxychloroquine make you sick?
In some people, HCQ may cause gastrointestinal problems, such as nausea, vomiting, upset stomach, cramps, or diarrhea. These may occur for the first few days a person takes the drug while the body adjusts to the medication.
What is the visual field of early Plaquenil toxicity?
Visual fields.
In early cases of Plaquenil toxicity, an early indicator of damage is the appearance of a paracentral scotoma seen on automated visual field testing in the absence of fundus changes.
Retinal Damage from Plaquenil | Hydroxychloroquine (Plaquenil) Side Effects and Testing
How common is eye damage from hydroxychloroquine?
Retinal toxicity from long-term hydroxychloroquine use is common, occurring in as many as 7.5% of patients.
What tests detect early eye damage?
Slit-Lamp Exam: Allows the optometrist to examine the structures at the front of your eye. Retinal Examination: Provides a detailed view of the back of the eye, including the retina and optic nerve. Tonometry: Measures the pressure inside your eyes, which is crucial for detecting glaucoma.
What are the worst side effects of hydroxychloroquine?
This medicine may cause muscle and nerve problems. Check with your doctor right away if you have muscle weakness, pain, or tenderness while using this medicine. Hydroxychloroquine may cause some people to be agitated, irritable, or display other abnormal behaviors within the first month after the start of treatment.
Why take hydroxychloroquine at night?
If HCQ gives you an energy boost, taking it at night may interfere with sleep quality. On the other hand, if nausea or cramping is your main concern, taking HCQ at night could help. The best way to figure out what works for you is to talk to your health care provider.
What happens if you suddenly stop taking hydroxychloroquine?
Suddenly stopping hydroxychloroquine (HCQ) significantly increases the risk of experiencing a severe relapse or flare-up of autoimmune symptoms, such as severe joint pain, muscle aches, and skin rashes. Because HCQ has a long half-life, symptoms might not reappear immediately, but rather over the course of weeks, as studies show that stopping the medication increases the likelihood of a flare by 61%.
How do you test for Plaquenil toxicity?
Plaquenil (hydroxychloroquine) toxicity screening is essential for patients on long-term therapy to prevent irreversible retinal damage. Current recommendations include a baseline eye exam within the first year, followed by annual screenings after 5 years of use, using specialized, objective tests like spectral-domain OCT (SD-OCT) and 10-2 visual fields.
What does hydroxychloroquine do to the brain?
Yes, hydroxychloroquine (HCQ) can affect the brain, as it is known to cross the blood-brain barrier and, in some cases, cause neuropsychiatric side effects. Reported adverse effects include anxiety, depression, mania, psychosis, and cognitive issues like confusion or memory problems. These are generally rare and, in some cases, linked to high-dose usage.
Can I skip a day of hydroxychloroquine?
It is generally safe to miss a single dose of hydroxychloroquine, but you should not make a habit of it. If you forget a dose, take it as soon as you remember, unless it is almost time for your next dose, in which case you should skip the missed dose and resume your regular schedule; never double a dose.
How toxic is hydroxychloroquine?
There have been pediatric deaths after ingesting as little as 1 to 2 tablets. It is estimated that 2 to 3 times the therapeutic dose can be fatal in less than three hours. Ingestions of 8 to 22g have caused life-threatening toxicity in adult patients.
What is OCT for Plaquenil toxicity?
Optical Coherence Tomography (OCT) is the primary objective tool used to screen for Plaquenil (hydroxychloroquine) toxicity. It detects the earliest structural damage to the retina long before irreversible vision loss or "bull's-eye" maculopathy occurs.
What are the symptoms of ocular toxicity?
Ocular toxicity symptoms range from mild irritation (dryness, redness, blurred vision) to severe vision loss or structural damage, often caused by medications, chemicals, or cancer treatments. Key warning signs include pain, light sensitivity (photophobia), halos, double vision, and sudden decreases in visual acuity or color vision.
What damage does hydroxychloroquine do?
severe skin reactions – causing symptoms such as spots, sores, blisters or peeling skin, as well as a high temperature and flu-like symptoms. vision problems (hydroxychloroquine retinopathy) – causing symptoms like constant blurred vision, changes to how you see colours or being sensitive to light.
What organ does hydroxychloroquine affect?
Hydroxychloroquine is metabolized in the liver and may alter metabolism of other medications. Therapy is unlikely to cause liver injury in normal individuals, but can trigger an acute worsening of porphyria cutanea tarda in susceptible individuals.
What should be monitored when taking hydroxychloroquine?
Key monitoring for hydroxychloroquine (HCQ/Plaquenil) focuses on detecting retinal toxicity and assessing renal/liver function. Essential screenings include annual eye exams (OCT and FAF) for long-term users, baseline blood work (CBC, ALT/AST, creatinine), and monitoring for muscle weakness or low blood sugar, typically every 3–6 months.
At what A1C does eye damage occur?
What causes diabetes-related retinopathy? Over time, high blood glucose (blood sugar) levels cause damage to the small blood vessels in the retina. Other factors, like smoking cigarettes, high blood pressure, or high cholesterol, can increase this damage. Keeping an A1C below 7% helps prevent retinopathy.
What are the first signs of MS in the eyes?
Early MS vision symptoms often stem from optic neuritis (inflammation of the optic nerve). Key signs include pain when moving the affected eye, blurry or dimmed vision (often described as looking through smudged sunglasses), faded colors, or temporary vision loss in one eye.
What is the 20 minute rule for eyes?
The "20-20-20 rule" is a simple, highly effective habit recommended by eye care professionals to prevent digital eye strain and Computer Vision Syndrome from prolonged screen time.
Can eye damage from Plaquenil be reversed?
Eye damage caused by Plaquenil (hydroxychloroquine), known as retinal toxicity or retinopathy, is generally not reversible. Once damage occurs, vision loss is often permanent and can sometimes continue to worsen for a period even after stopping the medication. Early detection through annual screening is critical to prevent severe, irreversible vision loss.
What are the long term side effects of hydroxychloroquine?
Long-term hydroxychloroquine (HCQ) use, often for conditions like lupus or rheumatoid arthritis, can lead to serious adverse effects, including retinal toxicity (vision changes), cardiomyopathy (weakened heart muscle), muscle weakness (myopathy), and rarely, nerve damage. The risk is strongly linked to high daily doses (>555 mg/kg/day) and treatment lasting over 5–10 years.
What does hydroxychloroquine retinopathy look like?
The retinopathy is manifest as damage to the photoreceptors and subsequent degeneration of the retinal pigment epithelium (RPE). This may produce a “Bull's eye maculopathy” and central visual loss. This is important as the only intervention to prevent further damage is stopping the drug.