We investigated the anti-craving effect of psychotropic analgesic nitrous oxide (PAN) in both an urban and rural community. Our results show that PAN, effectively eliminates or reduces craving in both cohorts in 98% of cases reporting craving. This positive effect is extremely rapid occurring within 40 minutes in patients withdrawing from alcohol, cannabis and nicotine. Although the concept of craving has been dogged by confusion and misunderstanding the idea is of practical importance because there appears to be a link between craving and relapse in patients who have a problem with substance abuse. The anti-craving effect of PAN may, therefore, be useful in preventing relapses in patients who abuse alcohol, nicotine and cannabis. Because PAN is an opioid it would seem that craving may be mediated by an underactivity of the endogenous opioid system. This work also confirms the safety and rapidity of the PAN therapy for treating addictive withdrawal states produced by alcohol, nicotine and cannabis. These findings confirm the usefulness of PAN as an investigative, diagnostic and therapeutic tool of the endogenous opioid system in man.