- current hospitalization - allergy to chloroquine or hydroxychloroquine - severe diarrhea and/or vomiting - significant hepatic impairment defined as known cirrhosis with history of hepatic encephalopathy or ascites. - prior retinal eye disease - concurrent malignancy requiring chemotherapy - known chronic kidney disease, stage 4 or 5 or dialysis. - known glucose-6 phosphate dehydrogenase (g6pd) deficiency. - known ventricular arrythmia, known prolonged qtc interval, or any known episode of sudden cardiac death - known porphyria - weight <40 kg - known pregnancy of breastfeeding - current use of chloroquine or hydroxychloroquine - current use of artemether, dapsone, lumefantrine or mefloquine - current use of cardiac medicines: amiodarone, digoxin, dofetilide, flecainide, procainamide, sotalol, or propafenone - current use of the following antimicrobials: levofloxacin, ciprofloxacin, moxifloxacin, azithromycin, clarithromycin, erythromycin, ketoconazole, or itraconazole - current use of the following antidepressants: amitriptyline, citalopram, desipramine, escitalopram, imipramine, doxepin, fluoxetine, sertraline, bupropion (wellbutrin), or venlafaxine - current use of the following antipsychotic or mood stabilizers: haloperidol, droperidol, lithium, quetiapine, thioridazine, ziprasidone - current use of methadone - current use of sumatriptan, zolmitriptan other than "as needed" - current use of systemic chemotherapy

- current hospitalization - allergy to chloroquine or hydroxychloroquine - severe diarrhea and/or vomiting - significant hepatic impairment defined as known cirrhosis with history of hepatic encephalopathy or ascites. - prior retinal eye disease - concurrent malignancy requiring chemotherapy - known chronic kidney disease, stage 4 or 5 or dialysis. - known glucose-6 phosphate dehydrogenase (g6pd) deficiency. - known ventricular arrythmia, known prolonged qtc interval, or any known episode of sudden cardiac death - known porphyria - weight <40 kg - known pregnancy of breastfeeding - current use of chloroquine or hydroxychloroquine - current use of artemether, dapsone, lumefantrine or mefloquine - current use of cardiac medicines: amiodarone, digoxin, dofetilide, flecainide, procainamide, sotalol, or propafenone - current use of the following antimicrobials: levofloxacin, ciprofloxacin, moxifloxacin, azithromycin, clarithromycin, erythromycin, ketoconazole, or itraconazole - current use of the following antidepressants: amitriptyline, citalopram, desipramine, escitalopram, imipramine, doxepin, fluoxetine, sertraline, bupropion (wellbutrin), or venlafaxine - current use of the following antipsychotic or mood stabilizers: haloperidol, droperidol, lithium, quetiapine, thioridazine, ziprasidone - current use of methadone - current use of sumatriptan, zolmitriptan other than "as needed" - current use of systemic chemotherapy