Ophiopogon japonicus, known as "Mai Men Dong" in traditional Chinese medicine (TCM), is primarily used for nourishing yin, moistening the lungs, and clearing heat. In classical TCM texts, it is not predominantly cited as a remedy for nausea and vomiting, but it is sometimes included in broader herbal formulas aimed at harmonizing the stomach and addressing gastrointestinal symptoms, including mild nausea, as part of its moistening and cooling roles. The actual mechanism proposed is indirect, focusing on balancing fluids and easing heat-induced digestive discomfort, rather than specifically targeting emesis or the nausea reflex itself.

Scientifically, there is limited evidence supporting Ophiopogon japonicus for the treatment of nausea or vomiting. While some pharmacological studies suggest anti-inflammatory and gastroprotective effects, these do not directly translate to antiemetic properties, and human clinical trials for nausea/vomiting specifically are lacking. Most references to its use in this context stem from traditional herbal compendia rather than modern pharmacology or randomized controlled trials. Therefore, its use for nausea and vomiting is justified mainly by traditional precedent rather than scientific data, and the supporting evidence is weak.