Giardia intestinalis is a protozoan parasite responsible for giardiasis, a diarrheal disease that affects roughly 280 million people annually. The parasite is transmitted through contaminated water, food, and direct human-to-human contact. Metronidazole is the primary drug used for treatment. However, an increasing resistance to metronidazole has been reported, and the underlying mechanisms behind this resistance remain unclear. As nitroreductase 1 is considered the primary activator of metronidazole, a deeper understanding of its role is essential for uncovering the mechanisms underlying metronidazole resistance. In this study, a vector containing the nitroreductase 1 gene was successfully constructed, and will be used in future experiments to investigate how its overexpression affects the Giardia phenotype. Furthermore, the rising incidence of resistance has intensified the search for alternative therapies. Here, 64 test compounds were screened for potential anti-Giardia activity. However, no significant inhibitory effects on Giardia growth were observed. The study highlights the need for further research into alternative anti-Giardia treatments and the metabolic role of nitroreductase 1.