 Lofexidine inhibits the release of norepinephrine in the central and peripheral nervous system, thereby reducing some of the symptoms of opioid withdrawal, but it has no documented effect on drug craving and endogenous opioid levels.Lofexidine's oral bioavailability is about 90%, with extensive oral absorption.Peak plasma concentrations occur at 3 hours after a single administration, with a half-life of 11 hours.