11 DESCRIPTION
Ropivacaine Hydrochloride Injection, USP is a sterile, isotonic solution that contains ropivacaine hydrochloride as the active pharmaceutical ingredient. Ropivacaine hydrochloride is a member of the amino amide class of local anesthetics. Ropivacaine Hydrochloride Injection, USP is administered parenterally by infiltration, epidural, and nerve block.
Ropivacaine hydrochloride is chemically described as S-(-)-1-propyl-2',6'-pipecoloxylidide hydrochloride monohydrate. The drug substance is a white crystalline powder, with the following structural formula:
C17H26N2O•HCl•H2O M.W. 328.89
At 25°C ropivacaine hydrochloride has a solubility of 53.8 mg/mL in water, a distribution ratio between n‑octanol and phosphate buffer at pH 7.4 of 14:1 and a pKa of 8.07 in 0.1 M KCl solution. The pKa of ropivacaine is approximately the same as bupivacaine (8.1) and is similar to that of mepivacaine (7.7). However, ropivacaine has an intermediate degree of lipid solubility compared to bupivacaine and mepivacaine.
Ropivacaine Hydrochloride Injection, USP is a clear, colorless, and preservative-free solution. Each mL contains 2.12 mg, 5.3 mg, 7.95 mg, or 10.6 mg ropivacaine hydrochloride monohydrate (equivalent to 2 mg, 5 mg, 7.5 mg, or 10 mg of ropivacaine hydrochloride anhydrous), and 8.6 mg, 8.0 mg, 7.5 mg, or 7.1 mg of sodium chloride, respectively, and sodium hydroxide and hydrochloric acid as pH adjusters, in water for injection. The specific gravity of Ropivacaine Hydrochloride Injection, USP solutions range from 1.002 to 1.005 at 25°C.