Naloxone Hydrochloride Injection, USP is a sterile, nonpyrogenic solution of naloxone hydrochloride in water for injection. Each milliliter (mL) contains 0.4 mg naloxone hydrochloride and sodium chloride to adjust tonicity in water for injection. May contain hydrochloric acid for pH adjustment; pH 4.0 (3.0 to 6.5).
The single-dose solution contains no bacteriostat, antimicrobial agent or added buffer (except for pH adjustment) and is intended for use only as a single-dose injection. When smaller doses are required, the unused portion should be discarded.
The multiple-dose solution contains, in addition, 1.8 mg/mL methylparaben and 0.2 mg/mL propylparaben added as preservatives.
Naloxone Hydrochloride Injection, USP may be administered intravenously, intramuscularly, or subcutaneously.
Naloxone, an opioid antagonist, is a synthetic congener of oxymorphone. It differs from oxymorphone in that the methyl group on the nitrogen atom is replaced by an allyl group.
Naloxone Hydrochloride, USP is chemically designated 17-Allyl-4,5α-epoxy-3,14-dihydroxymorphinan-6-one hydrochloride (C19H21NO4 • HCl), a white to slightly off-white powder soluble in water, in dilute acids, and in strong alkali; slightly soluble in alcohol; practically insoluble in ether and chloroform. It has a molecular weight of 363.84. It has the following structural formula: