Affecting more than half of menstruating women, dysmenorrhea is a cramp which causes abdominal or lower back pain just before or during a menstruation. In western medicine, non-steroidal anti-inflammatory drugs (NSAIDs) are normally used to treat primary dysmenorrheal symptoms. Despite their rapidity in relieving pain, NSAIDs have many serious side effects on the liver, kidney, and gastrointestinal tract. Thai traditional medicines comprise many preparations for treating dysmenorrhea, especially Prasaplai preparation which has been listed in the Thai traditional common household drug list since 2006. The use of Prasaplai was originated about 100 years ago and is still being used in the present time to treat dysmenorrhea. This review focuses on the history of the preparation, active ingredients, and biological activities especially on cyclooxygenase inhibitor, artifacts occurred in the preparation, quantitative analysis, and clinical trial of Prasaplai formulation.