Lupus and Antimalarials
posted in Treatment of Lupus on February 10, 2026 by
Updated January 28, 2026
Lupus and antimalarials share a surprising and life-saving connection. While antimalarials were first used to fight malaria, doctors now prescribe them to treat lupus symptoms, and for good reason.
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Systemic lupus erythematosus (SLE) is a chronic autoimmune disease. It causes the immune system to attack healthy tissues, leading to inflammation, pain, and long-term damage. This can affect the skin, joints, kidneys, lungs, heart, and brain.
One of the most effective drugs for managing lupus is hydroxychloroquine, an antimalarial. It helps reduce symptoms, prevent flares, and protect vital organs.
What Are Antimalarials?
A Brief History
Antimalarials were originally developed to prevent and treat malaria. Over time, doctors discovered that these medications offered powerful benefits for autoimmune diseases, including lupus.
As Dr. Donald Thomas explains, patients often ask why malaria drugs help lupus. He notes, “Patients sometimes ask, ‘Why do drugs used to treat malaria also work for autoimmune diseases like lupus?’” The answer lies in how the immune system processes antigens and produces antibodies.
Hydroxychloroquine, commonly known by the brand name Plaquenil, became the most widely used antimalarial for lupus. Today, it remains a cornerstone of lupus treatment worldwide.
How Antimalarials Work
Antimalarials work by calming the immune system without shutting it down. This distinction matters greatly for people with lupus.
In lupus, the immune system mistakenly attacks the body’s own tissues. Antimalarials interfere with this process at a critical step. As described in the Lupus Encyclopedia, macrophages and other antigen-presenting cells normally digest antigens in acidic vacuoles. These cells then activate T-cells, which signal B-cells to produce autoantibodies.
When antimalarials enter these cells, “they concentrate inside the vacuoles and create higher pH levels.” Because of this change, “the APCs’ digesting enzymes are unable to function,” and harmful autoantibody production decreases.
Dr. Thomas emphasises that this effect does not weaken immune defence. “We call HCQ an immunomodulator and not an immunosuppressant. It calms down the immune system without suppressing it.”
Antimalarials also block abnormal toll-like receptor activity. These receptors drive inflammation in lupus, so blocking them reduces disease activity.
Why Are Antimalarials Used for Lupus?
Reducing Inflammation
Lupus causes inflammation throughout the body. Antimalarials reduce inflammation in the joints, skin, blood, and internal organs.
According to the Lupus Encyclopedia, these drugs “help arthritis, rashes, serositis, fatigue, fevers, and low blood counts.” As a result, many patients experience less pain and better daily function.
Preventing Disease Flares
Hydroxychloroquine significantly lowers flare frequency. Dr. Thomas cites a Canadian study showing that “73% of patients who did not take an antimalarial medicine developed flares,” compared with only 36% of those who did.
Moreover, flares tend to be milder in patients taking antimalarials consistently. This makes long-term disease control more achievable.
Protecting Organs
Antimalarials protect organs by limiting inflammation early. This protection reduces long-term damage, especially in the kidneys.
Between 40% and 50% of people with lupus develop lupus nephritis. Dr. Thomas explains that people who take hydroxychloroquine regularly are less likely to develop kidney disease, and if it does occur, it is often less severe.
Lowering Blood Clot Risk
Blood clots remain a major concern in lupus. Antimalarials reduce this risk substantially.
A Canadian study showed that lupus patients taking antimalarials were “68% less likely to develop blood clots.” This benefit applies even to patients without antiphospholipid antibodies.
Improving Skin and Joint Symptoms
Antimalarials are especially effective for lupus rashes and arthritis. They also reduce UV sensitivity, although sun protection remains essential.
Dr. Thomas notes that hydroxychloroquine “reduces skin UV sensitivity,” but it does not replace sunscreen or sun avoidance.
Long-Term Benefits of Lupus and Antimalarials
Increased Survival
One of the strongest reasons to use antimalarials involves survival. As Dr. Michelle Petri states, “Hydroxychloroquine is the only drug proven to prolong survival in lupus.”
Multiple studies support this claim. A Canadian study found that patients not taking hydroxychloroquine were four times more likely to die than those who did.
Another large study concluded, “Antimalarials are the only class of drugs that exerted a clear protective effect on survival.”
Reduced Steroid Dependence
Antimalarials reduce the need for long-term steroids. This effect matters because steroids cause serious side effects.
Dr. Thomas explains that steroids can cause infections, heart failure, ulcers, and organ damage. Using hydroxychloroquine allows doctors to lower steroid doses and shorten treatment duration.
Improved Quality of Life
When lupus remains controlled, patients feel better physically and emotionally. Antimalarials improve energy, reduce pain, and support daily functioning.
The Lupus Encyclopedia lists “improve quality of life” among the many benefits of antimalarial therapy.
Are There Risks to Using Antimalarials?
Hydroxychloroquine has an excellent safety profile. Most patients tolerate it well.
Dr. Thomas emphasises, “With HCQ having so many good effects, it is impressive that it rarely causes severe side effects.”
Common Side Effects
Some people experience mild symptoms, including:
Nausea
Diarrhoea
Headaches
Skin discoloration
“These are typically mild and tolerable or go away when the dose is decreased,” Dr. Thomas explains.
Eye Safety and Retinal Toxicity
The most serious concern involves the retina. Over time, antimalarials can accumulate in retinal tissue.
However, risk remains low. “Only an estimated 2% of patients taking HCQ for 10 years have retinopathy,” according to the Lupus Encyclopedia.
Modern screening makes serious vision loss preventable. Dr. Thomas reassures readers, “Vision problems from antimalarials should not occur” when current eye exam guidelines are followed.
Lupus and Antimalarials During COVID-19
During the COVID-19 pandemic, hydroxychloroquine became controversial. Increased demand led to shortages.
Many lupus patients could not access their medication. Some experienced flares after missing doses. This period highlighted how essential antimalarials are for lupus care.
Later studies confirmed hydroxychloroquine does not treat COVID-19. However, its role in lupus remains unquestioned.
Should Antimalarials Be Taken Long Term?
Most experts recommend lifelong use unless true allergy exists. Stopping hydroxychloroquine often leads to flares, even during remission.
“Everyone with SLE should be taking antimalarials if they are not truly allergic.”
In rare cases, dose reduction may occur under supervision. However, stopping completely is usually discouraged.
Access to Antimalarials Worldwide
Access varies globally. Cost and supply issues limit availability in some regions.
Patient advocacy groups continue to push for equitable access. Lifesaving medications should not depend on geography or income.
Why Lupus and Antimalarials Matter
Antimalarials form the foundation of lupus treatment. They reduce inflammation, prevent flares, protect organs, and extend life.
As Dr. Thomas summarises, “The medicine’s many advantages far outweigh any risk of significant side effects.”
With proper dosing and monitoring, hydroxychloroquine remains one of the safest and most effective tools in lupus care.
For more in-depth information on Lupus and Antimalarials:
Read more in The Lupus Encyclopedia, edition 2
Look up your symptoms, conditions, and medications in the Index of The Lupus Encyclopedia
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