[Substitutional relations in the expression of drug consumption].

The present paper analyzes the formal equivalence of expressing the consumption of medicines in financial and physical units. The study was carried out on a representative sample of population; for the sake of the need of analytical expression also the factor of the age in the consumption of drugs measured per 1 inhabitant was taken into consideration. A highly close relationship between the two specific variables is observed. On this basis the postulate of the validity of equivalence is formulated. The paper points to the stability of this formal equivalence also in the conditions of the action of the seasonal component and the pragmatic significance of the obtained results for pharmaco-epidemiological studies is stressed.