Betamethasone sodium phosphate injection and preparation method and application thereof

The invention belongs to the field of medicines, and particularly relates to a betamethasone sodium phosphate injection and a preparation method and application thereof. Every 1000 milliliters of the injection comprises: 5-6 grams of betamethasone sodium phosphate; 0.09 to 0.15 g of disodium edetate; 6 to 8 g of disodium hydrogen phosphate; a proper amount of 1% phosphoric acid solution; and water for injection, which is added to 1000mL. The preparation method of the injection comprises the following steps: preparing the betamethasone sodium phosphate, the edetate disodium, the disodium hydrogen phosphate and 1% phosphoric acid solution according to the formula amounts; adding a proper volume of water for injection into a liquid preparation tank, introducing nitrogen for bubbling, then sequentially adding and dissolving the components, and supplementing the water for injection to the formula amount to obtain a liquid medicine; and processing the liquid medicine through a sterilization filter, and filling the