The antidote for nitrite poisoning is methylene blue, also commonly known as methylene blue. Nitrite has a strong oxidizing property, oxidizing the divalent iron hemoglobin in the blood into trivalent iron hemoglobin, trivalent iron hemoglobin can’t be combined with oxygen, hemoglobin loses its function of transporting oxygen, thus causing tissue and organ hypoxia, and a series of systemic hypoxia symptoms appear. As a reducing agent, Meilan can effectively reduce trivalent ferrohemoglobin to divalent ferrohemoglobin, thus restoring the ability of hemoglobin to transport oxygen, and effectively relieving the function of nitrite poisoning.