Endotoxins, primarily lipopolysaccharides from Gram-negative bacteria, pose serious risks to patients, causing fever, shock, or even fatal reactions. The Bacterial Endotoxin Test (BET), aligned with USP <85>, EP 2.6.14, and IP 2.6.14, uses Limulus Amebocyte Lysate (LAL) assays to detect pyrogenic contamination. Techniques include gel clot, kinetic turbidimetric, and chromogenic assays. BET is mandatory for injectable products, implantable devices, and other parenteral materials, ensuring patient safety and regulatory compliance.