Abstract: The present invention provides composition of matter for and methods of treating pain and drug abuse using novel chimeric hybrid molecules containing an opioid moiety of chemically modified morphine (3) that binds to and activates the human mu (?) opioid receptor, with the opioid moiety linked through a novel linker-hinge (4) to a substance P peptide fragment moiety (5) that binds to and activates the human substance P receptor. The hybrid alkaloid/peptide chimeric molecules produce clinically efficacious opioid analgesia with little or no development of opioid tolerance or formation of opioid dependence. The hybrid alkaloid/peptide analgesics may be administered intrathecally, systemically or orally.