Resistance to currently available antimalarial drugs has been confirmed in only two of the four human malaria parasite species, first developed independently in three to four areas in Southeast Asia, Oceania, and South America in the late 1950s and early 1960s. Since then, chloroquine resistance has spread to nearly all areas of the world where falciparum malaria is transmitted. Chloroquine raises ph Chloroquine disadvantages Plaquenil and myasthenia gravis Plaquenil sulfate allergy Nomura T, Carlton JM, Baird JK, del Portillo HA, Fryauff DJ, Rathore D, et al. Evidence for different mechanisms of chloroquine resistance in 2 Plasmodium species that cause human malaria. J Infect Dis. 2001; 153–61. Chloroquine is a 4-aminoquinoline with antimalarial, anti-inflammatory, and potential chemosensitization and radiosensitization activities. Although the mechanism is not well understood, chloroquine is shown to inhibit the parasitic enzyme heme polymerase that converts the toxic heme into non-toxic hemazoin, thereby resulting in the accumulation of toxic heme within the parasite. The precise mechanism by which Chloroquine exhibits activity is not known. Chloroquine, may exert its effect against Plasmodium species by concentrating in the acid vesicles of the parasite and by inhibiting polymerization of heme. It can also inhibit certain enzymes by its interaction with DNA. Although resistance to these drugs tends to be much less widespread geographically, in some areas of the world, the impact of multi-drug resistant malaria can be extensive. Has also developed resistance to nearly all of the other currently available antimalarial drugs, such as sulfadoxine/pyrimethamine, mefloquine, halofantrine, and quinine. Mechanism of resistance to chloroquine Molecular mechanisms involved in chloroquine resistance., Chloroquine C18H26ClN3 - PubChem Chloroquine heme polymeraseWhat is retinopathy hydroxychloroquine Chloroquine – Resistance In Plasmodium Falciparum. With cholorquine there is emergence of resistance, which has limited its use. Primarily highly effective against febrile illness, relief is quickly achieved within 24 hours. It is easily available, well tolerated and cost effective but now uses are declining because of resistance. 1. Chloroquine – howMed. Chloroquine - FDA prescribing information, side effects.. Chloroquine Mechanism of action and resistance in malaria.. The major action of chloroquine is to inhibit the formation of hemozoin Hz from the heme released by the digestion of hemoglobin Hb. The free heme then lyses membranes and leads to parasite death. Chloroquine resistance is due to a decreased accumulation of chloroquine in the food vacuole. The mechanisms of resistance for amino‐alcohols quinine, mefloquine and halofantrine are still unclear. Epidemiological studies have established that the frequency of chloroquine resistant mutants varies among isolated parasite populations, while resistance to antifolates is highly prevalent in most malarial endemic countries. Chloroquine is a 9-aminoquinoline known since 1934. Apart from its well-known antimalarial effects, the drug has interesting biochemical properties that might be applied against some viral infections. Chloroquine exerts direct antiviral effects, inhibiting pH-dependent steps of the replication of several viruses including members of the flaviviruses, retroviruses, and coronaviruses. Its best.