Phyllanthus urinaria has a longstanding history of use in traditional medicine systems, particularly in Asia, for addressing parasitic infections, including intestinal worms (nematodes). Ethnobotanical surveys and traditional pharmacopeias from countries such as China, India, and Southeast Asian nations cite the use of P. urinaria preparations (decoctions, juices, powders) for expelling intestinal worms and supporting gastrointestinal health. The rationale for such use is rooted in empirical observations rather than scientific validation.

Scientifically, there are only a handful of in vitro or animal studies investigating the antiparasitic activity of P. urinaria. Some laboratory research has reported that extracts from the plant exhibit moderate activity against certain helminths, but these results are preliminary and not consistently replicated. There is a lack of robust clinical studies in humans confirming efficacy or safety for this indication. Thus, while traditional use is well documented, the evidence from controlled laboratory or clinical research remains limited and inconclusive.

In summary, the use of Phyllanthus urinaria for nematode or worm infestations is primarily justified by tradition, with anecdotal efficacy and sparse scientific investigation. Caution is warranted due to the lack of high-quality evidence supporting its use for this purpose.