Mefloquine hydrochloride

Mefloquine hydrochloride is a quinoline antimalarial drug that is structurally related to the antiarrhythmic agent quinidine. Mefloquine inhibited KvLQT1/minK channel currents with an IC50 value of approximately 1 microM. Mefloquine hydrochloride inhibits several mutant hemichannel forms implicated in KID syndrome when expressed in Xenopus laevis oocytes (IC50∼16 μM), using an extracellular divalent cation, zinc (Zn++), as a nonspecific positive control for comparison (IC50∼3 μM). Mefloquine slowed the activation rate of KvLQT1/minK and more block was evident at lower membrane potentials compared with higher ones.