EMETINE & DEHYDROEMETINE
Emetine, an alkaloid derived from ipecac, and dehydroemetine, a synthetic analog, are effective against tissue trophozoites of E histolytica, but because of major toxicity concerns their use islimited to unusual circumstances in which severe amebiasis requires effective therapy and metronidazole cannot be used. Dehydroemetine is preferred because of its somewhat better toxic-ity profile. The drugs should be used for the minimum period needed to relieve severe symptoms (usually 3–5 days) and should be administered subcutaneously (preferred) or intramuscularly in a supervised setting. Emetine and dehydroemetine should not be used intravenously. Adverse effects, which are generally mild with use for 3–5 days, increase over time and include pain, tenderness, and sterile abscesses at the injection site; diarrhea, nausea, and vomiting; muscle weakness and discomfort; and minor electrocar-diographic changes. Serious toxicities include cardiac arrhythmias, heart failure, and hypotension. The drugs should not be used in patients with cardiac or renal disease, in young children, or in pregnancy unless absolutely necessary.