Induction of albendazole resistance in Giardia lamblia.

Previous studies have shown that Giardia lamblia resistance to metronidazole can be induced in the laboratory, and treatment failures with this drug have also been documented. As replacement therapies, anthelmintic benzimidazoles have antigiardial activity with few clinical side effects. Albendazole has the greatest antigiardial activity of anthelmintic benzimidazoles tested and is effective in vivo. Although Chavez et al. failed to subculture albendazole-exposed G. lamblia, some patient isolates have shown decreased in vitro sensitivity to this drug. In this study, in vitro resistance to albendazole was induced in G. lamblia by a method similar to that reported by Townson et al.