Possible Interaction: Quinine and Halofantrine

“Qinghaosu derivatives were more efficient than other antimalarial drugs, but a positive correlation was observed between the 50% inhibitory concentrations of halofantrine and quinine and the number of adhesive parasitized red blood cells, suggesting their influence on cytoadherence.”

“The response to halofantrine was positively correlated with the responses to quinine and mefloquine, in the case of chloroquine and halofantrine an inverse relationship was observed.”

“In conclusion, we showed that quinine and quinidine coadministered with HF might inhibit its metabolism resulting in the potentiation of HF-induced cardiotoxicity in patients.”

“Mefloquine, quinine , quinidine, and ketoconazole used at maximal plasma concentrations inhibited N-debutylhalofantrine formation noncompetitively with Ki values of 70 microM, 49 microM, 62 microM, and 0.05 microM resulting in 7%, 49%, 26%, and 99% inhibition, respectively, in HF metabolism.”

“A marked resistance to halofantrine is shown by parasites resistant to mefloquine, quinine , chloroquine and amodiaquine, although the moderately chloroquine-resistant 'NS line' is sensitive.”