The invention provides a preparation method of a
famotidine preparation for injection, and relates to the technical field of medicaments. The method comprises the following steps: s1, weighing a prescription amount of
aspartic acid, adding a proper amount of water for injection, keeping the liquid preparation temperature within the range of 20-30 DEG C, performing stirring to dissolve the asparticacid, sequentially adding prescription amounts of
famotidine,
mannitol and
poloxamer-188, and adding the water for injection to full
dose; s2, adding
activated carbon, and performing stirring at normal temperature, wherein the dosage of the
activated carbon is 0.1% (g / mL) of the total amount of the liquid
medicine; and s3, after sterilization,
filtration and split charging, adopting a rubber plughalf-pressure plug of which the
drying weight loss is controlled to be 0.15% or below after cleaning and sterilization, and performing freeze-
drying according to set freeze-
drying parameters. According to the invention,
moisture can be kept stable in the storage period, the main
drug dissolving speed can be increased, and the liquid preparation time is obviously shortened.