The invention relates to a
lacosamide injection and a preparation method thereof. The injection contains
lacosamide, a stabilizer, an
antioxidant, a complexing agent and a
buffer solution. The injection is characterized in that the stabilizer is
sodium gluconate, the
antioxidant is
sodium pyrosulfite,
alpha tocopherol and
glutathione, the complexing agent is
edetate disodium, and the
buffer solution is an
acetic acid-
sodium acetate
buffer solution. Meanwhile, the invention discloses a corresponding preparation method. Compared with the prior art, the preparation method has the advantages that the stability of
lacosamide is obviously improved, particularly, the generation of two main impurities, namely an
impurity D (N-deacetylated lacosamide
hydrochloride) and an
impurity F (demethylated lacosamide), can be obviously reduced, the quality of a preparation product is improved, the toxic and side effects are reduced, and the preparation method is simple, low in cost and suitable for industrial production. The method is suitable for industrial large-scale production.