• To test the efficacy of an alpha- and beta -adrenergic blocker, carvedilol, in reducing cocaine use in methadone maintained cocaine users and to test whether the efficacy of carvedilol is moderated by cocaine withdrawal severity. [ Time Frame: Four years ] [ Designated as safety issue: No ]
  

The adrenergic neurotransmission serves multiple functions including learning, emotional processing and stress response to psychological and physical challenges (Huether, 1996; Sved et al., 2001). Adrenergic transmission also mediates drug withdrawal states and stress-induced relapse to drug use (Aston-Jones et al., 2004; Stewart, 2000). Consistent with these preclinical findings, adrenergic blockers showed promise as a treatment of cocaine dependence (Kampman et al., 2001b; Kampman et al., 2006). These preliminary findings are significant because there are no proven pharmacotherapies for cocaine addiction although an estimated 2.3 million of Americans aged 12 or older are regular cocaine users (SAMHSA, 2004). The societal cost of cocaine addiction is estimated to be $45 billion in the US, suggesting that development of even modestly effective cocaine pharmacotherapies will have great economic benefits. For example, availability of a medication decreasing cocaine use by 10 percent is estimated to have $745 million economic benefit in the US alone (Cartwright, 2000). Thus, developing effective treatments for cocaine addiction is an essential goal with significant benefits both for the society and the individual.

This study is active and enrollment is continuing.