Abstract

In order to learn something of their respective addiction characteristics (a) dihydromorphine, (b) dihydrodesoxymorphine-D, (c) dihydrodesoxycodeine-D, and (d) methyldihydromorphinone were each substituted for morphine in four successive groups of addicted patients. Addiction satisfaction by the first three drugs was nearly complete. However, with methyldihydromorphinone satisfaction was incomplete and neither slightly larger amounts nor somewhat shorter intervals of administration improved this.

The relative intensities of their dependence effects, as estimated from the corrected amounts of equivalent single doses, and expressed as reciprocals, were: morphine 1/50, (a) 1/14.75, (b) 1/10.1, (c) 1/69.9, and (d) 1/6.9. The durations of their dependence effects also varied considerably: morphine 14.4 hours, (a) 19.2 hours, (b) 4.5 hours, (c) 8.5 hours, and (d) 4.5 hours.

These variations in intensity and duration of physical dependence effect are undoubtedly the results of alterations in chemical structure. When the components of physical dependence effect and of analgetic action have been identified with particular characteristics of the morphine molecule, it should be possible to vary them so as to produce a drug having a long and strong analgetic action, but a short and weak dependence effect. Such a drug would be ideal for clinical purposes.