Dehydroemetine

Dehydroemetine is an alkaloid related to emetine, derived from ipecac and produced by dehydrogenation of emetine. It has been used as an antiprotozoal agent for amoebiasis, particularly infections caused by Entamoeba histolytica. Historically it served as a treatment for severe amoebic dysentery and as an alternative when standard nitroimidazole therapy was unavailable or not tolerated. In modern practice its use is limited, and it remains a second- or third-line option in some settings under strict medical supervision due to toxicity.

Mechanism of action: Dehydroemetine inhibits protein synthesis in protozoa by binding to the eukaryotic 40S ribosomal subunit, which disrupts translocation during translation and impairs parasite growth. Because the drug can affect human ribosomes at higher exposures, it requires careful handling and monitoring.

Safety and side effects: The major risk associated with dehydroemetine is cardiotoxicity, including arrhythmias, myocarditis, and congestive heart failure, which can be dose- and duration-dependent. Other adverse effects may include nausea, vomiting, hypotension, and electrocardiographic abnormalities. Due to these risks, therapy is typically performed under close clinical and, when possible, electrocardiographic monitoring, and the drug is generally avoided in patients with preexisting heart disease or significant electrolyte disturbances.

Availability and status: Dehydroemetine is not widely used in contemporary practice and is largely restricted to particular regions or clinical scenarios. It is often superseded by safer and more effective therapies, such as metronidazole with a luminal agent, in the treatment of amoebiasis. See also emetine and ipecac.