Effects of addiction to intravenous heroin on patterns of physical activity in man

Abstract

Physical activity measurements were made during 30 days of placebo administration followed by 60 days of addiction to intravenous heroin. The experimental design was double‐blind. Five prisoner addicts served as subjects. The daily measures of activity selected were: (a) hours lying horizontal on the bed, (b) hours of sleep, (c) hours off the research ward, and (d) miles recorded on a pedometer.The several activity measurements correlated well. The experiments indicate that techniques may be used to measure major daily activities which require minimal directed participation by the subject and which do not Significantly influence degree and quality of activity. Compared with placebo, heroin increased activity when given in single intravenous doses or in repeated doses for 3 or 4 days, but depressed activity when chronically administered over a longer interval. When patients chronically received heroin they showed a pronounced tendency to retreat from all forms of activity and social contacts, and to go to their rooms to lie alone on their beds, eyes closed, frequently with radios turned on, “nodding” (sedated, but usually not sleeping).Clinical observations and pursuit rotor tests indicate that the depressant effects on activity observed during chronic heroin administration were not due to debility or to psychomotor impairment but rather suggest a reduced responsiveness of the patient to ambient stimuli.