The necessary intensification of the information activity in the pharmacy service raises the question of the demand of each drug on the pharmacist as regards its information volume. The wealth of information on the application of drugs necessitates their differentiation and systematization. One differentiates between basic and additional information. On determining the frequency of occurrence of 21 pieces of additional information concerning 1321 pharmaceutical preparations, the mean information content according to Shannon [17] is calculated. The quantified results determine drug information as a statistical quantity from which their semantics for the receiver (user of the drug) must be abstracted. To consider the aspects concerning the contents and function of additional information, the weighting coefficients of 85 drug groups were calculated (by means of the triangular matrix method), and introduced. It is suggested to combine the numerical values of the statistically defined amounts of information with the quantities deduced from the meaningfulness in a parameter of the informational potential (IP) of pharmaceutical preparations. Finally, the authors convey their ideas of the benefit from, and the possible uses of, the IP.