Genetic Implications:
Pronunciation:
hye-drox-ee-klor-oh-kwin
Trade Name(s)
Ther. Class.
antimalarials
(DMARDs)
Inhibits protein synthesis in susceptible organisms by inhibiting DNA and RNA polymerase.
Therapeutic Effect(s):
Spectrum:
Active against chloroquine-sensitive strains of: Plasmodium falciparum, Plasmodium malariae, Plasmodium ovale, and Plasmodium vivax.
Absorption: Highly variable (31–100%) following oral administration.
Distribution: Widely distributed; high concentrations in RBCs; crosses the placenta; excreted into breast milk.
Metabolism and Excretion: Partially metabolized by the liver to active metabolites; partially excreted unchanged by the kidneys.
Half-life: 40 days.
TIME/ACTION PROFILE (plasma concentrations)
ROUTE | ONSET | PEAK | DURATION |
---|---|---|---|
PO | rapid† | 1–2 hr | days–wk |
Contraindicated in:
Use Cautiously in:
CV: QT interval prolongation, heart block, HF, TORSADES DE POINTES
Derm: acute generalized exanthematous pustulosis, alopecia, DRUG REACTION WITH EOSINOPHILIA AND SYSTEMIC SYMPTOMS (DRESS), ERYTHEMA MULTIFORME, hair color changes, hyperpigmentation, photosensitivity, pruritus, rash, STEVENS-JOHNSON SYNDROME (SJS), TOXIC EPIDERMAL NECROLYSIS, urticaria
EENT: corneal deposits, nystagmus, retinopathy, tinnitus, vertigo, visual disturbances
Endo: hypoglycemia
GI: ↑ liver enzymes, abdominal pain, anorexia, diarrhea, HEPATOTOXICITY, nausea, vomiting
GU: proteinuria
Hemat: AGRANULOCYTOSIS, APLASTIC ANEMIA, leukopenia, thrombocytopenia
Metabolic: ↓ weight
Neuro: aggressiveness, anxiety, ataxia, dizziness, dyskinesia, dystonia, fatigue, headache, irritability, neuromyopathy, nightmares, peripheral neuritis, personality changes, psychoses, SEIZURES, SUICIDAL THOUGHTS/BEHAVIORS, tremor
Resp: bronchospasm, PULMONARY HYPERTENSION
Misc: ANGIOEDEMA
* CAPITALS indicate life-threatening.
Underline indicate most frequent.
Drug-Drug
Malaria
PO (Adults): Prophylaxis: 400 mg once weekly; start 2 wk prior to entering malarious area; continue for 4 wk after leaving area. Treatment: 800 mg initially, then 400 mg at 6 hr, 24 hr, and 48 hr after initial dose.
PO (Children ≥31 kg): Prophylaxis: 6.5 mg/kg (not to exceed 400 mg) once weekly; start 2 wk prior to entering malarious area; continue for 4 wk after leaving area. Treatment: 13 mg/kg (not to exceed 800 mg) initially, then 6.5 mg/kg (not to exceed 400 mg) at 6 hr, 24 hr, and 48 hr after initial dose.
Rheumatoid Arthritis
PO (Adults): 400–600 mg per day in 1–2 divided doses; once adequate response obtained, may ↓ dose to maintenance dose of 200–400 mg per day in 1–2 divided doses.
Lupus Erythematosus
PO (Adults): 200–400 mg per day in 1–2 divided doses.
Tablets: 100 mg, 200 mg, 300 mg, 400 mg
Assess deep tendon reflexes periodically to determine muscle weakness. Therapy may be discontinued should this occur.
Monitor for signs and symptoms of DRESS (fever, rash, lymphadenopathy, and/or facial swelling, associated with involvement of other organ systems (hepatitis, nephritis, hematologic abnormalities, myocarditis, myositis) during therapy. May resemble an acute viral infection. Eosinophilia is often present. Discontinue therapy if signs occur.
Assess for rash periodically during therapy. May cause SJS. Discontinue therapy if severe or if accompanied with fever, general malaise, fatigue, muscle or joint aches, blisters, oral lesions, conjunctivitis, hepatitis and/or eosinophilia.
Assess for suicidal tendencies, depression, or changes in behavior periodically during therapy.
Lab Test Considerations:
Monitor CBC and platelet count periodically during therapy. May cause decreased RBC, WBC, and platelet counts. If severe decreases occur that are not related to the disease process, discontinue hydroxychloroquine .
Do not confuse hydroxychloroquine with hydrochlorothiazide or hydroxyurea.
Caution patient to keep hydroxychloroquine out of reach of children; fatalities have occurred with ingestion of 3 or 4 tablets.
Advise patient to notify health care professional promptly if sore throat, fever, unusual bleeding or bruising, blurred vision, visual changes, ringing in the ears, difficulty hearing, or muscle weakness occurs.
Review methods of minimizing exposure to mosquitoes with patients receiving hydroxychloroquine prophylactically (use repellent, wear long-sleeved shirt and long trousers, use screen or netting).