Semi-quantitative near-patient tests with fixed standard thresholds for deficient, intermediate and normal glucose-6-phosphate dehydrogenase (G6PD) activity should be used to inform administration of specific treatment regimens. The dose of 1 mg/kg/day primaquine for 7 days or single dose tafenoquine should only be given to those above the threshold that corresponds to >70% of normal G6PD activity; and 0.5 mg/kg/day primaquine for 14 days or 0.5 mg/kg/day primaquine for 7 days can be given to those with a threshold that corresponds to > 30% of normal G6PD activity to prevent relapses of P. vivax and P. ovale.