From the Guidelines
Plaquenil (hydroxychloroquine) is primarily used to treat rheumatoid arthritis, as recommended by the 2021 American College of Rheumatology guideline for the treatment of rheumatoid arthritis 1.
Key Points
- Plaquenil is a disease-modifying antirheumatic drug (DMARD) that reduces inflammation by interfering with toll-like receptor signaling and reducing cytokine production.
- The typical dosage ranges from 200-400mg daily, with treatment continuing long-term.
- Regular eye exams are necessary while taking Plaquenil due to the small risk of retinal toxicity, especially with long-term use or higher doses.
- Blood monitoring is also typically performed to check for other potential side effects.
Arthritis Conditions Treated by Plaquenil
- Rheumatoid arthritis (RA)
- Systemic lupus erythematosus (SLE), which often involves arthritis symptoms
- Other inflammatory arthritis conditions, although the evidence for these is not as strong, and Plaquenil is not recommended for psoriatic arthritis (PsA) 1.
Important Considerations
- Plaquenil has a relatively slow onset of action, often taking 2-3 months to show full benefits.
- It is often used in combination with other medications for arthritis treatment, such as sulfasalazine and methotrexate, as part of a triple therapy regimen 1.
- The 2019 American College of Rheumatology guideline for the treatment of juvenile idiopathic arthritis also mentions the use of hydroxychloroquine as a DMARD, although it is not the primary treatment recommended 1.
From the FDA Drug Label
Rheumatoid Arthritis, Systemic Lupus Erythematosus and Chronic Discoid Lupus Erythematosus The mechanisms underlying the anti-inflammatory and immunomodulatory effects of hydroxychloroquine sulfate in the treatment of rheumatoid arthritis, chronic discoid lupus erythematosus and systemic lupus erythematosus are not fully known.
Hydroxychloroquine treats the following types of arthritis:
- Rheumatoid Arthritis: Hydroxychloroquine is used to treat rheumatoid arthritis, although the exact mechanisms of its anti-inflammatory and immunomodulatory effects are not fully understood 2. Note that the provided text does not mention other types of arthritis.
From the Research
Arthritis Treatment with Plaquenil
Plaquenil, also known as hydroxychloroquine (HCQ), is used to treat various types of arthritis, including:
- Rheumatoid arthritis (RA) 3, 4, 5
- Systemic lupus erythematosus (SLE) 3, 6, 5
- Osteoarthritis (OA) 3
- Sjögren's syndrome 3, 5
Mechanism of Action
The exact mechanism of action of HCQ in treating arthritis is not fully understood, but it is believed to:
- Accumulate in lysosomes and autophagosomes of phagocytic cells 3, 5
- Affect MHC Class II expression and antigen presentation 3
- Reduce production of pro-inflammatory cytokines 3, 5
- Protect against cytokine-mediated cartilage resorption 3
Efficacy and Safety
HCQ has been shown to be effective in treating mild to moderate RA and SLE, with a good safety profile 3, 4, 6. However, its use can be associated with ocular toxicity, and regular monitoring is recommended 3, 6. The daily dose of HCQ should not exceed 5 mg/kg/day actual body weight to minimize the risk of retinal toxicity 6.