From the Guidelines
Hydroxychloroquine (HCQ) is recommended for all patients with Systemic Lupus Erythematosus (SLE) at a daily dose not exceeding 5 mg/kg real body weight, with regular eye examinations necessary to monitor for retinal toxicity, as evidenced by the 2019 update of the EULAR recommendations for the management of SLE 1. The primary use of HCQ is in the treatment of SLE, where it has been shown to have multiple beneficial effects, including reducing disease activity and preventing damage accrual.
- Key benefits of HCQ in SLE include:
- Reduction of disease symptoms and signs
- Prevention of damage accrual
- Minimization of drug side-effects
- Improvement of quality of life
- The recommended daily dose of HCQ should not exceed 5 mg/kg real body weight, as this has been shown to minimize the risk of retinal toxicity, with a prevalence of retinal abnormalities exceeding 10% after 20 years of continuous use 1.
- Regular eye examinations are necessary to monitor for retinal toxicity, with baseline testing advised to rule out confounding disease when a patient is started on HCQ, and annual screening with sensitive tests beginning no more than 5 years after treatment initiation 1.
- The risk of retinal toxicity from HCQ is <2% for usage up to 10 years at a daily dosage of ≤5 mg/kg/day actual body weight, and widespread adoption of more sensitive testing techniques will allow the detection of early toxicity and thus preserve the patient’s visual function 1.
From the FDA Drug Label
Hydroxychloroquine sulfate tablets are an antimalarial and antirheumatic indicated for the: Treatment of uncomplicated malaria due to Plasmodium falciparum, Plasmodium malariae, Plasmodium ovale, and Plasmodium vivax in adult and pediatric patients. Prophylaxis of malaria in geographic areas where chloroquine resistance is not reported in adult and pediatric patients. Treatment of rheumatoid arthritis in adults. Treatment of systemic lupus erythematosus in adults. Treatment of chronic discoid lupus erythematosus in adults.
The use of Hydroxychloroquine (HCQ) is for the treatment and prophylaxis of certain conditions, including:
- Malaria: treatment of uncomplicated malaria and prophylaxis in areas where chloroquine resistance is not reported
- Rheumatoid arthritis: treatment in adults
- Systemic lupus erythematosus: treatment in adults
- Chronic discoid lupus erythematosus: treatment in adults 2 2
From the Research
Uses of Hydroxychloroquine (HCQ)
- HCQ is an antimalarial drug indicated in the treatment of acute attacks of malaria due to Plasmodium vivax, P. malariae, P. ovale, and susceptible strains of P. falciparum 3
- It is also used for the treatment of rheumatoid arthritis, discoid and systemic lupus erythematosus 3, 4, 5, 6
- HCQ has been proposed in COVID-19 therapy, although its effectiveness and safety for this use are still being debated 3, 7
- It has also been shown to be a disease-improving agent for the treatment of other rheumatic diseases, including antiphospholipid syndrome and primary Sjögren's syndrome 5
Administration and Stability
- HCQ is typically available in tablet form, but a liquid formulation has been developed for easier administration in pediatric and geriatric patients, and patients unable to swallow 3
- The liquid formulation has been shown to be chemically and microbiologically stable for at least 6 months under various storage conditions 3
Safety and Adverse Effects
- HCQ can cause adverse reactions, including retinal toxicity, and clinicians should carefully monitor patients with rheumatism when prescribing these drugs 4, 5, 6
- The risk of adverse events associated with HCQ use, particularly when combined with azithromycin, may outweigh the potential clinical benefits in patients with COVID-19 7
- HCQ-induced toxicity can affect various organs, including the eye, heart, muscle, nerves, inner ear, and kidney, and most of these side effects are reversible if treatment is stopped promptly 6