Hydroxychloroquine
Hydroxychloroquine
Plaquenil; mostly prescribed generically
Experience
No personal reports yet
No clinical reports yet
Log in to add your own experience.
Problems
No problems yet. Be the first to suggest one.
+ Add a problemTitration strategies
No titration strategies yet. Be the first to suggest one.
Effects
No effects listed yet. Be the first to suggest one.
Relevant anecdote
No anecdotes yet. Share a relevant one.
Relevant Literature
No literature entries yet.
Log in to submit relevant literature.
Summary
Common uses
Rheumatoid arthritis0, Systemic lupus erythematosus0, Discoid and subacute cutaneous lupus0, Sjögren's syndrome0, Malaria treatment and prophylaxis (chloroquine-sensitive areas)0
Pharmacy
Starting dose
200-400 mg PO daily; dose by actual body weight ≤5 mg/kg/d to reduce retinopathy risk (AAO 2016 guideline)
Preparations
200 mg tablets; 100 mg/5 mL suspension
US FDA Max
400 mg/d typical maintenance; weight-adjusted ceiling per ophthalmology guidance
Pharmacology
Routes
Oral
Onset
Rheumatologic effect at 6-12 weeks
Duration
Weeks (long half-life)
Half-life
~40 days (terminal; reflects extensive tissue distribution)[1]
Bioavailability
70-75% (oral)[1]
Pregnancy
Long-considered safe in pregnancy for lupus and other rheumatologic indications; benefits typically outweigh.[citation needed]
Legal status
Rx-only in US
Purported mechanism
Hydroxychloroquine accumulates in lysosomes (lysosomotropic weak base), raising lysosomal pH and impairing endolysosomal antigen processing and TLR7/9 endosomal signaling; the net effect dampens innate immune activation and reduces autoantibody production in lupus and inflammation in rheumatoid arthritis.0 Retinal toxicity is the dose- and duration-limiting adverse effect (bull's eye maculopathy with photoreceptor damage); the 2016 American Academy of Ophthalmology guideline established the ≤5 mg/kg actual-body-weight ceiling and baseline + annual screening starting at year 5[1]. QT prolongation and rare cardiomyopathy are recognized cardiac risks. The 2020 COVID-19 controversy is documented separately; HCQ does not have established benefit in COVID-19 and was eventually withdrawn from active recommendation.
References
- ↑ 1.0 1.1 1.2 FDA Prescribing Information, Plaquenil (hydroxychloroquine sulfate), Sanofi-Aventis, current revision. https://www.accessdata.fda.gov/drugsatfda_docs/label/2017/009768s048lbl.pdf