12. history of drug abuse within 1 year prior to the first day of dose administration, as judged by the Investigator and/or has a positive urine drug screen for substances of abuse including marijuana, cocaine, amphetamines, opiates, phencyclidine, barbiturates, benzodiazepines, propoxyphene, methadone metabolites, and cannabinoids and tricyclin anti-depressants at screening or on admission to the study centre;