Praziquantel (Standard) is the standard substance of Praziquantel, and it is applicable for quantitative analysis, quality control, and related research in biochemical experiments. Praziquantel (Droncit) increases the permeability of the tegument of susceptible worms, resulting in an influx and increase in intra-tegumental calcium leading to rapid contractions and paralysis of the worm's musculature through a subsequent increase in levels of calcium in the sarcoplasmic reticulum. Praziquantel is a pyrazinoisoquinoline derivative with anthelminthic property. In addition, vacuolization of the tegumental syncytium and blebbing results in tegument disintegration, leads to antigen exposure and elicit host defense responses to the worm.