SPL Set ID: b8e48063-0b40-ee43-85c1-4ef2de80c404

Butorphanol tartrate is a synthetically derived opioid agonist-antagonist analgesic of the phenanthrene series. The chemical name is (-)-17-(cyclobutylmethyl)morphinan-3,14-diol[S-(R*,R*)]-2,3-dihydroxybutanedioate (1:1) (salt). The molecular formula is C 21 H 29 NO 2 •C 4 H 6 O 6 , which corresponds to a molecular weight of 477.55 g/mol and the following structural formula: Butorphanol tartrate is a white crystalline substance. The dose is expressed as the tartrate salt. One milligram of the salt is equivalent to 0.68 mg of the free base. The n-octanol/aqueous buffer partition coefficient of butorphanol is 180:1 at pH 7.5. Butorphanol tartrate nasal spray, USP is an aqueous solution of butorphanol tartrate for administration as a metered spray to the nasal mucosa. Each bottle of butorphanol tartrate nasal spray, USP contains 2.5 mL of a 10 mg/mL solution of butorphanol tartrate with sodium chloride, citric acid, and benzethonium chloride in purified water with sodium hydroxide and/or hydrochloric acid added to adjust the pH to 5. The pump reservoir must be fully primed [see PATIENT INSTRUCTIONS ] prior to initial use. After initial priming each metered spray delivers an average of 1 mg of butorphanol tartrate and the 2.5 mL bottle will deliver an average of 14 to 15 doses of butorphanol tartrate nasal spray, USP. If not used for 48 hours or longer, the unit must be reprimed [see PATIENT INSTRUCTIONS ] . With intermittent use requiring repriming before each dose, the 2.5 mL bottle will deliver an average of 8 to 10 doses of butorphanol tartrate nasal spray, USP depending on how much repriming is necessary.