Amebicidal properties

McCowen MC, Callender ME, Lawlis JF Jr. (1951) Fumagillin (H-3), a new antibiotic with amebicidal properties. Science 113 202-203. 

Niridazole possesses both schistosomicidal and amebicidal properties. In addition, it has antiinflammatory properties... 

Paromomycin, an aminoglycoside with antibacterial and amebicidal properties, is indicated in the treatment of acute and chronic intestinal amebiasis, of tapeworm (fish, beef, pork, and dog) infections in patients who cannot take praziquantel or niclosamide, and as an adjunctive regimen in the management of hepatic coma. 

Ipecac alkaloids are derived from the amino acid tyrosine and the monoterpene secologanin and are therefore termed terpenoid-isoquinoline alkaloids. They occur in the eudicot families Alangiaceae and Rubiaceae. Two species, Psychotria ipecacuanha (Rubiaceae) and Alangium lamarckii (Alangiaceae), have been investigated in detail with respect to their metabolites and biosynthesis of their alkaloids (Fujii and Ohba, 1998). Roots and rhizomes of P. ipecacuanha are the source of cephaeline and emetine (Fig. 9), two compounds with emetic, expectorant, and amebicidal properties. 

Thus the main quality of chloroquine that exceeds all other antimalarial drug is its effect on erythrocytic schizonts (hematoschizotropic action). However, chloroquine also possesses amebicidal action. It has also been observed to have immunodepressive and antiarrhythmic properties. 

Iodoquinol (diiodohydroxyquin) is a halogenated hydroxy-quinoline. It is an effective luminal amebicide that is commonly used with metronidazole to treat amebic infections. Its pharmacokinetic properties are poorly understood. Ninety percent of the drug is retained in the intestine and excreted in the feces. The remainder enters the circulation, has a half-life of 11-14 hours, and is excreted in the urine as glucuronides. 

Emetine (Fig. 7-9) in the form of the crude drug obtained from the roots and rhizomes of Ipecac (Cephaelis ipecacuanha) has been in use since the seventeenth century. The alkaloid, as the hydrochloride, has been used parenterally to treat amebic dysentery. It is also effective in hepatic infestation, but not against amebic cysts. Because of its cardiac toxicity and emetogenic properties, it has been superseded by metronidazole and chloroquine, but it is still used as an alternative. The amebicidal mechanism of emetine is protein synthesis inhibition by interference of peptidyl-RNA translocation. Since this action is general to eukaryotic cells, its relative selectivity in the presence of mammalian cells is not well understood. Unrelated uses of Ipecac (presumably due to its alkaloid content) are as an expectorant in cough preparations and an emergency emetic (Syrup of Ipecac). 

Describe the pharmacodynamic and pharmacokinetic properties of the major amebicides tdilox-anide, emetine, iodoquinol, and metronidazole). List other clinical applications of metronidazole. Identify the drugs useful for prophylaxis and treatment of pneumocystosis and toxoplasmosis and know their toxic effects. 

Some reports have stated berberine sulfate to be amebicidal, and trypanocidal and berbamine, isotetrandine, and hydroxya-canthine to have hypotensive properties (glasby 1 martindale). ... 

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