"More controversially, adding customised opioids, enkephalinase-inhibitors and kappa-antagonists to our therapeutic armamentarium may prove critical to boosting response- and remission-rates towards 100% in the decades ahead. Crudely, whereas dopamine mediates "wanting", mu opioid agonists mediate "liking". Both systems can be fruitfully enhanced. Depressive and dysthymic people often suffer from a dysfunctional opioid system and anhedonia - an incapacity to experience pleasure. Sometimes orthodox "antidepressants" may even make them feel worse. Yet controlled clinical trials of designer narcotics for refractory and/or melancholic depression, let alone their use by "normal" people with "ordinary" mood-disorders, are not imminent."

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