Primaquine Mefloquine

Antimalarial drugs are designed to prevent or treat malaria. Antimalarial drugs currently used for treatment for prophylaxis are mefloquine, primaquine, chloroquine, pyrimethamine, amodiaquin, quinine/quinidine, chloroguanide. 

Chemoprophylaxis for travelers to geographic regions where chloroquine-resistant P falciparum is endemic is best provided by (A) Atovaquone Mefloquine Primaquine... 

Malaria, a tropical disease caused by protozoan parasites of the genus Plasmodium, has been a major concern for centuries and has now extended to a great deal of the world s population, killing every year 1-2 million people. Different medicines are in use to cure or to prevent malaria. The classical natural medicine quinine was soon replenished with synthetic compounds such as primaquine, chloroquine and mefloquine. However, a major problem is still an increasing resistance towards these compounds. 

VI.a.2.1. AminoquinoUnes. The aminoquinolines currently used as antimalarials include the 4-amino-quinolines chloroquine and mefloquine and the 8-aminoquinoline primaquine. 

Non-falciparum malaria (like P. vivax) can still be treated with chloroquine although chloroquine resistant P. vivax has been reported from Irian Jaya and Papua New Guinea. In those areas treatment with mefloquine is recommended. To treat the liverstages an additional 2-3 weeks treatment with primaquine is given. It appears that tafenoquine (dosed once a week), a new 8-aminoquinoline, would be a better replacement for primaquine in preventing relapses in P. vivax malaria. 

Quinoline derivatives chloroquine phosphate hydroxychloroquine sulfate mefloquine hydrochloride primaquine phosphate... 

Mefloquine is effective in prophylaxis against most strains of P falciparum and probably all other human malarial species. Mefloquine is therefore among the drugs recommended by the CDC for chemoprophylaxis in all malarious areas except for those with no chloroquine resistance (where chloroquine is preferred) and some rural areas of Southeast Asia with a high prevalence of mefloquine resistance. As with chloroquine, eradication of P vivax and P ovale requires a course of primaquine. 

Primaquine has been studied as a daily chemoprophylactic agent. Daily treatment with 30 mg (0.5 mg/kg) of base provided good levels of protection against falciparum and vivax malaria. However, potential toxicities of long-term use remain a concern, and primaquine is generally recommended for this purpose only when mefloquine, Malarone, and doxycycline cannot be used. 

Clinical Use. Primaquine is typically used to treat the relapses of specific forms of malaria,12 and is generally administered in acute or severe exacerbations, or when other drugs (chloroquine, mefloquine) are ineffective in suppressing malarial attacks. Primaquine may also be used to prevent the onset of malaria in individuals who are especially at risk because of prolonged exposure to the disease.50 This drug is administered orally. 

Peytavin et al. [17] have reported on the chiral resolution of mefloquine, halofantrine, enpiroline, quinine, quinidine, chloroquine, and primaquine by subcritical fluid chromatography on a (S) naphthylurea column (250 X 4.6 mm ID). The mobile phase consisted of carbon dioxide, methanol, and triethylamine at a 3-ml/min flow rate. Except for primaquine and... 

Quinine, mefloquine, chloroquine, artesunate, artemether and primaquine (gametocytocides) act on sexual forms and prevent transmission of the infection because the patient becomes noninfective and the parasite fails to develop in the mosquito (site 4). 

Mefloquine, chloroquine, proguanil, and pyrimethamine plus dapsone (Maloprim), alone or in combination are most commonly advised for prophylaxis regimens and doxycycline for special cases (drug resistance or intolerance) primaquine is being re-evaluated. 

The chemotherapeutic response of Plasmodium berghei to various combinations of mefloquine with other drugs (sulfadoxine + pyrimethamine, primaquine, floxacrine) have shown that the desired effects are purely additive (SEDA-13, 809), so the adverse effects too are probably only those of the individual compounds. Adverse reactions occurred in 46% of 400 patients treated with Fanimef (mefloquine + pyrimethamine + sulfadoxine) (SEDA-12, 693). Of note were dizziness (29%), nausea (9.5%), vomiting (7.3%), weakness/lassitude (5.8%), abdominal discomfort or pain (5.5%), diarrhea (3.8%), pruritus (3.0%), insomnia (2.0%), and headache (2.0%). 

Schwartz E, Regev-Yochay G. Primaquine as prophylaxis for malaria for nonimmune travelers A comparison with mefloquine and doxycycline. Clin Infect Dis I999 29(6) 1502-6. Lobel HO, Coyne PE, Rosenthal PJ. Drug overdoses with antimalarial agents prescribing and dispensing errors. JAMA 1998 280(17) 1483. 

Quinine, chloroquine, amodiaquine, amopyroquine, hydroxychloroquine, primaquine, mefloquine, proguanil, chlorproguanil, cycloguanil, sulfadiazine, sulfalene, sulfadoxine, dap... 

The DNA-binding hypothesis has also been proposed for the action of acridines, 4-aminoquinolines (eg. Chloroquine), 8-aminoquinolines (Primaquine) and qui-nolinemethanols (quinine, mefloquine), which has recently been reviewed [150-152]. 

Schwartz E, Regev-Yochay G. Primaquine as prophylaxis for malaria for nonimmune travelers A comparison with mefloquine and doxycydine. Clin Infect Dis 1999 29 1502-1506. 

Synthetic antimalarials developed fiom herbals include chloroquine, primaquine, proguanil, pyrimethamine and mefloquine. Botanicals represent a diverse arsenal of molecules that could constitute lead compounds for new antimalarial dmgs, such as artemisinin, isolated from Artemisia annuaSeveral studies have been undertaken to evaluate the inhibitory effects of various plants extracts on P. falciparum in culture. The in vivo antiplasmodial effects of several plant extracts have been studied on Plasmodium berghei and P. yoelii The majority of the plants that we screened for antimalarial activities had similar ethnopharmacological use among different Kenyan ethnic groups. ... 

Photosensitized polymerization of lens proteins can be selected as a measure of eye phototoxicity (Chapter 11). Proteins isolated from calf lens are suitable to simulate the conditions in the human eye. The reaction mechanisms can be evaluated by adding various quenchers to the reaction medium during irradiation. Chloroquine, hydroxychloroquine, mefloquine, and quinacrine induced polymerization under the given experimental conditions (Kristensen et al., 1995). These compounds have a large apparent distribution volume and a long elimination half-life and must therefore be considered as potential photosensitizers in the eye. Primaquine and quinine were also shown to induce polymerization of lens proteins in vitro but are less likely to reach the eye in vivo due to fast elimination from the body. 

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