II. Indications

  1. Early Rheumatoid Arthritis
    1. Especially Antinuclear Antibody positive
  2. Systemic Lupus Erythematosus
  3. Malaria Prophylaxis and treatment
    1. Regions without Chloroquine resistance, non-severe infections
  4. Rheumatologic off-label uses
    1. Dermatomyositis
    2. Sjogren Syndrome
    3. Sarcoidosis
  5. Infectious off-label uses
    1. Q Fever
  6. NOT indicated in COVID-19 outside of clinical trials
    1. Initial studies as of May 2020 suggest no benefit and adverse effect risk (including QTc Prolongation)

III. Mechanism

  1. Antimalarial agent used in rheumatic disease
  2. Modified Chloroquine to reduce Retinopathy risk

IV. Efficacy

  1. Response in 70-80% of cases
  2. Response occurs in 3-6 months
  3. Highest efficacy when used early in disease process

V. Dose: Rheumatologic Disorders

  1. Varies significantly based on use
    1. Lower doses are used in infectious disease
  2. Initial: 200 mg orally twice daily
  3. Taper after 1-2 years when stable: 200 mg PO qd

VI. Adverse Effects

  1. Eye-related Adverse Effects
    1. Epithelial Keratopathy and other Corneal disorders
    2. Retinopathy
      1. Rare (contrast with Chloroquine)
  2. Neurologic adverse effects
    1. Early toxicity (subsides within 2 weeks)
      1. Irritability
      2. Insomnia
      3. Headache
    2. Late toxicity requires medication discontinuation
      1. Tinnitus
      2. Decreased Hearing acuity
    3. Very rare toxicity
      1. Myopathy or muscular weakness
    4. Other adverse effects
      1. Confusion or Delirium
      2. Extrapyramidal Side Effects
      3. Hallucinations
  3. Gastrointestinal adverse effects
    1. Increased stool frequency
    2. Diarrhea
    3. Bloating
    4. Nausea
  4. Endocrine Adverse Effects
    1. Hypoglycemia
  5. Hematologic Adverse Effects
    1. Neutropenia
    2. Pancytopenia
  6. Cardiovascular adverse effects
    1. Palpitations
    2. Premature Atrial Contractions
    3. QTc Prolongation (with risk of Ventricular Tachycardia or Drug-Induced Torsades de Pointes)
      1. Increased risk when combined with other agents causing QTc Prolongation (e.g. Azithromycin)

VII. Monitoring

  1. Routine Eye Exam every 6-12 months

VIII. References

Images: Related links to external sites (from Bing)

Related Studies

Cost: Medications

hydroxychloroquine (on 5/17/2017 at Medicaid.Gov Survey of pharmacy drug pricing)
HYDROXYCHLOROQUINE 200 MG TAB Generic $0.56 each
plaquenil (on 10/20/2016 at Medicaid.Gov Survey of pharmacy drug pricing)
PLAQUENIL 200 MG TABLET Generic $0.56 each

Ontology: Hydroxychloroquine (C0020336)

Definition (NCI) A 4-aminoquinoline with immunosuppressive, antiautophagy, and antimalarial activities. Although the precise mechanism of action is unknown, hydroxychloroquine may suppress immune function by interfering with the processing and presentation of antigens and the production of cytokines. As a lysosomotropic agent, hydroxychloroquine raises intralysosomal pH, impairing autophagic protein degradation; hydroxychloroquine-mediated accumulation of ineffective autophagosomes may result in cell death in tumor cells reliant on autophagy for survival. In addition, this agent is highly active against the erythrocytic forms of P. vivax and malariae and most strains of P. falciparum but not the gametocytes of P. falciparum.
Definition (NCI_NCI-GLOSS) A substance that decreases immune responses in the body. It is used to treat some autoimmune diseases, and is being studied as a treatment for graft-versus-host disease. Hydroxychloroquine belongs to the family of drugs called antiprotozoals.
Definition (MSH) A chemotherapeutic agent that acts against erythrocytic forms of malarial parasites. Hydroxychloroquine appears to concentrate in food vacuoles of affected protozoa. It inhibits plasmodial heme polymerase. (From Gilman et al., Goodman and Gilman's The Pharmacological Basis of Therapeutics, 9th ed, p970)
Definition (PDQ) A 4-aminoquinoline with antimalarial and immunosuppressive properties. Although its precise mechanism of action is unknown, hydroxychloroquine may suppress immune function by interfering with the processing and presentation of antigens and the production of cytokines. This agent is highly active against the erythrocytic forms of P. vivax and malariae and most strains of P. falciparum but not the gametocytes of P. falciparum. Check for "http://www.cancer.gov/Search/ClinicalTrialsLink.aspx?id=38571&idtype=1" active clinical trials or "http://www.cancer.gov/Search/ClinicalTrialsLink.aspx?id=38571&idtype=1&closed=1" closed clinical trials using this agent. ("http://nciterms.nci.nih.gov:80/NCIBrowser/ConceptReport.jsp?dictionary=NCI_Thesaurus&code=C557" NCI Thesaurus)
Concepts Pharmacologic Substance (T121) , Organic Chemical (T109)
MSH D006886
SnomedCT 373540008, 83490000
LNC LP16163-5, MTHU016851
English Hydroxychlorochin, Hydroxychloroquine, Oxychlorochin, Oxychloroquine, ethanol, 2-((4-((7-chloro-4-quinolinyl)amino)pentyl)ethylamino)-, Hydroxychloroquine [Chemical/Ingredient], HYDROXYCHLOROQUINE, hydroxychloroquine, Hydroxychloroquine (product), Hydroxychloroquine (substance), HCQ
Swedish Hydroxiklorokin
Czech hydroxychlorochin
Finnish Hydroksiklorokiini
Russian GIDROKSIKHLOROKHIN, OKSIKHLOROKHIN, PLAKVENIL, ГИДРОКСИХЛОРОХИН, ОКСИХЛОРОХИН, ПЛАКВЕНИЛ
Polish Hydroksychlorochina
Japanese オキシクロロキン, ヒドロキシクロロキン
Spanish hidroxicloroquina (producto), hidroxicloroquina (sustancia), hidroxicloroquina, Hidroxicloroquina, Oxicloroquina
French Hydroxychloroquine
German Hydroxychlorochin, Hydroxychloroquin, Oxychlorochin, Oxychloroquin
Italian Idrossiclorochina
Portuguese Hidroxicloroquina, Oxicloroquina

Ontology: Plaquenil (C0699177)

Concepts Pharmacologic Substance (T121) , Organic Chemical (T109)
MSH D006886
English Plaquenil Sulfate, plaquenil sulfate, plaquenil, Plaquenil