Macroeconomic aspects of substance abuse: diffusion, productivity and optimal control

This paper deals dynamically with macroeconomic aspects of widespread substance abuse with a reference to illicit drugs as an example. Substance-abuse impedes the productivity of the labour force and subsequently economic growth. The labour force is divided into non-using and therefore fully productive workers, a number of whom are employed by the government in drug-control activities, and drug users who are only partially productive. An efficient management of the nation’s portfolio of workers is taken to be the trajectory of drug-control that maximises the present value of the stream of disposable national incomes.