CV: arrhythmias (including sinus bradycardia, sinus arrhythmia, first degree AV block, abnormal T waves), ECG changes, syncope.
Derm: rash.
EENT: tinnitus.
GI: abdominal pain, diarrhea, nausea, vomiting (↑ in children).
Neuro: dizziness, fatigue, neuropsychiatric symptoms, vertigo.
Therapeutic Classification: antimalarials
Pharmacologic Classification: quinine analogues
Absorption: Well absorbed following oral administration.
Distribution: Extensive tissue distribution including parasitized erythrocytes; crosses the placenta, minimal excretion in breast milk.
Protein Binding: 98%.
Metabolism/Excretion: Extensively metabolized by the liver (primarily by the CYP3A4 enzyme system), metabolites do not have antimalarial activity. Excreted mostly in bile and feces as metabolites. Small amounts excreted in urine.
Half-life: 2–4 wk.
20 kg): Mild-to-moderate malaria — 20–25 mg/kg (may be split into two doses 6–8 hr apart, if vomiting occurs, all or part of the dose may be repeated); patients with acute P. vivax should also be subsequently treated with an 8–aminoquinoline; prophylaxis — 5 mg/kg once weekly (for patients >45 kg — use one 250 mg tablet, if 30–45 kg — use 3/4 tablet, if 20–30 kg — use 1/2 tablet) beginning one wk before arrival in endemic area (sooner if concurrent medications decrease tolerance) and continued for 4 wk after returning.