L-Histidine is widely used in pharmaceutical formulations, particularly in parenteral nutrition, where it supports protein synthesis and tissue repair in patients who cannot obtain sufficient nutrients through diet. It serves as a precursor for histamine, a compound involved in immune responses, digestion, and neurotransmission, making it valuable in treatments related to immune regulation and allergic response studies. In biotechnology and laboratory settings, L-Histidine is used as a buffer component due to its ability to maintain stable pH levels, especially in protein purification and enzyme assays. Its metal-chelating properties make it useful in cell culture media and in the stabilization of therapeutic proteins and antibodies. It is also incorporated into some eye drops and wound healing formulations due to its role in tissue protection and antioxidant activity. In infant nutrition, especially in formula development, L-Histidine is added to support growth and neurological development, mimicking the composition of human breast milk.