Last reviewed 2026-04-22 · How we verify

Hydroxychloroquine reduced

Hydroxychloroquine is a quinoline antimalarial and immunomodulatory agent that inhibits lysosomal function and reduces inflammatory cytokine production.

Hydroxychloroquine is a quinoline antimalarial and immunomodulatory agent that inhibits lysosomal function and reduces inflammatory cytokine production. Used for Rheumatoid arthritis, Systemic lupus erythematosus, Malaria prophylaxis and treatment.

At a glance

Mechanism of action

Hydroxychloroquine accumulates in lysosomes and impairs autophagy and antigen presentation, thereby suppressing T-cell and B-cell activation. It also inhibits toll-like receptor signaling and reduces production of pro-inflammatory cytokines such as TNF-α and IL-6, making it effective in autoimmune and inflammatory conditions.

Approved indications

• Rheumatoid arthritis
• Systemic lupus erythematosus
• Malaria prophylaxis and treatment
• Discoid lupus erythematosus

Common side effects

• Retinopathy
• Nausea and gastrointestinal upset
• Headache
• Dizziness
• Pruritus
• Myopathy

Key clinical trials

• Hydroxychloroquine (HCQ) in Pediatric Interstitial Lung Disease (ILD) (PHASE2)
• Effect of HCQ Combined With LT4 on LBR in Euthyroid Women With URPL and TPO-Ab (NA)
• Sorafenib Induced Autophagy Using Hydroxychloroquine in Hepatocellular Cancer (PHASE2)
• SKIN Disease Profiling by an Exploratory, pRospective, Biomarker Study in dermatoloGY Practice (SKINERGY)
• Effectiveness of an EHR Interface to Reduce Dosage of Hydroxychloroquine (NA)
• a Retrospective Study on the Systemic Treatment of LPP and FFA
• Hydroxychloroquine in ANCA Vasculitis Evaluation (PHASE4)
• Evaluation of Hydroxychloroquine to Prevent CIPN (PHASE2)

Primary sources

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