Table 1.

Main pharmacodynamic properties of antimalarials.

	Hydroxychloroquine (HCQ)	Chloroquine (CQ)	Quinacrine
Chemical structure
Chemical formula	C18H26ClN3O	C18H26ClN3	C23H30ClN3O
Way of administration	Oral intake
Absorption	In upper intestinal tract after a 200 mg oral dose, HCQ reached a Cmax of 129.6 ng/ml with a Tmax of 3.26 h in the blood 18	In upper intestinal tract oral CQ reaches a Cmax of 65–128 µg/L with a Tmax of 0.5 h 19	In upper intestinal tract more details not available
Bioavailability	67–74% 20	67–100% 19	Not available
Volume of distribution	5522 liters from blood and 44,257 liters from plasma 20	200–800 L/kg 19	Not available
Protein binding	50% 20	46–74% 21	80–90% 22
Metabolism	In the liver, N-dealkylated by CYP3A4 to the active metabolite desethylhydroxychloroquine, as well as the inactive metabolites desethylchloroquine and bidesethylchloroquine17,18	In the liver, N-dealkylated primarily by CYP2 C8 and CYP3A4 to N-desethylchloroquine N-dealkylated to a lesser extent by CYP3A5, CYP2D6, and to an ever lesser extent by CYP1A119	Not available
Elimination	40–50% of HCQ is excreted renally, while only 16–21% of a dose is excreted in the urine as unchanged drug 5% of a dose is sloughed off in skin and 24–25% is eliminated through the feces19,20	Predominantly eliminated in the urine, renal excretion: 65–70%. 24 50% of a dose is recovered in the urine as unchanged CQ, with 10% of the dose recovered in the urine as desethylchloroquine 19	Less than 11% is eliminated in the urine daily 28
Elimination half-life	Historically, 40–50 days (chronic use) A 200 mg oral dose of HCQ: 537 h to 50 days (blood) or 32 days or 123 days in plasma18,23 Maybe shorter, about 5 days, according to more recent studies25,26	6–60 days (mean of 20 days)19,24	5–14 days