Sodium hypochlorite (NaOCI) is used extensively as an artificial exsheathment medium of nematode larvae in a diversity of studies such as comparing the efficacy of drugs, assessment of resistance to anthelmintics or evaluation of plant extracts as anthelmintics by virtue of its unique capacity for tissue dissolution. Tests with NaOCI indicate that the compound, although highly effective as exsheathing agent, the infectivity of the exsheathed larvae produced was significantly low suggesting reduced viability. We used Strongyloides papillosus larvae, a nematode that naturally lacks a protective sheath and a potentially highly motile organism, as a model to exclude or confirm possible negative effects on the viability of the parasite. Motility was taken as a viability assay. Larvae were designated as actively motile, sluggish, or immotile. Results were presented as supplementary movie files. The viability of larvae is dependent on both the concentration and the time of exposure to the compound. There are certain concentration (C) and time (T) limits beyond which viability is impaired (0.3% ˃ C ˃ 0.2%; 10 min ˃ T ˃ 5 min). The results support the conclusions from infectivity tests that where NaOCI is used as an exsheathment medium, results should be interpreted with caution as the compound is potentially capable of reducing the viability of larvae. It may even induce structural damage.