REVEX (nalmefene hydrochloride injection), an opioid antagonist, is a 6-methylene analogue of naltrexone. The chemical structure is shown below:

Molecular Formula: C₂₁H₂₅NO₃· HCl

Molecular Weight: 375.9, CAS # 58895-64-0

Chemical Name: 17-(Cyclopropylmethyl)-4,5 -epoxy-6-methylenemorphinan-3,14-diol, hydrochloride salt.

Nalmefene hydrochloride is a white to off-white crystalline powder which is freely soluble in water up to 130 mg/mL and slightly soluble in chloroform up to 0.13 mg/mL, with a pKa of 7.6.

REVEX is available as a sterile solution for intravenous, intramuscular, and subcutaneous administration in two concentrations, containing 100 mg or 1.0 mg of nalmefene free base per mL. The 100 mg/mL concentration contains 110.8 mg of nalmefene hydrochloride and the 1.0 mg/mL concentration contains 1.108 mg of nalmefene hydrochloride per mL. Both concentrations contain 9.0 mg of sodium chloride per mL and the pH is adjusted to 3.9 with hydrochloric acid.

Concentrations and dosages of REVEX are expressed as the free base equivalent of nalmefene.

Bookmark this page: