Artemisinins (or artemisinin derivatives)
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Artesunate, artemether and dihydroartemisinin
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The most widely used of the anti-malarial drugs with very short half-lives. These are sub-curative in standard 3 day regimens if used as monotherapies
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Antifolates
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Pyrimethamine, chlorproguanil, proguanil, sulphadoxine and dapsone
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The combination sulphadoxine-pyrimethamine (SP; also known by its trade name ‘Fansidar’) is widely used for therapy. Both constituents have long half-lives so it was given as a single-dose regimen but resistance quickly evolved. Its use is now primarily restricted to treatment/prophylaxis in intermittent treatment programmes
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4-aminoquinolines
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Chloroquine, amodiaquine, piperaquine, pyronaridine and naphthoquine
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Chloroquine was used in huge quantities as a monotherapy for over 30 years. Resistance occurred only infrequently and Africa never developed its own resistance instead it was aquired by immigrations from South-East Asia
[42].
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Arylamino alcohols
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Quinine, mefloquine, lumefantrine and halofantrine
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Quinine was the first anti-malarial to be identified. A long treatment duration and its safety profile means it is now mainly used in early pregnancy or as a (parenteral) second-line treatment either alone or in combination in uncomplicated or severe malaria. Lumefantrine with artemether is currently the most widely used anti-malarial combination therapy; it has low-level antagonistic resistance with chloroquine
[43].
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Naphthalenes
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Atovaquone
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Atovaquone is active against hepatic and asexual stages but resistance arises spontaneously at very high rates. Has synergistic pharmacodynamics when combined with proguanil, resistance no longer occurs at high rates and the combination therapy widely used as prophylaxis under the trade-name ‘Malarone’. Can also be used curatively but high cost restricts its deployment in resource-poor health services.
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8-aminoquinolines
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Primaquine and tafenoquine
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These drugs affect hepatic and transmission stages but do not affect the pathogenic asexual stages of the plasmodium cycle so are not routinely uses to cure acute infections. Both are toxic in glucose-6-phosphate dehydrogenase deficient patients
[44]. Primaquine has a short half-life which reduces its therapeutic effectiveness but means concentration can be allowed to drop very rapidly in patients identified with adverse reactions.
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Antibiotics |
Tetracycline |
These drugs do have activity against the asexual stages but their slow speed of action precludes their use as therapeutics |