A contribution to the kinetics of dissolution of some modern drugs

A report is presented on the investigation of some drugs being used in modern therapy from the point of view of dissolution kinetics in aqueous and in aqueous micellar solutions. It has been established that the dissolution (saturation) process, in accordance with previous assumptions, is kinetically of the first order both in aqueous and in aqueous micellar solutions. The rate constants describing these processes are nearly identical for the same drug, hence the saturation rates are nearly identical. The amount of drug dissolved within the unit of time decreases in the case of drotaverine and "RJ-64" in direct proportion to the concentration of the surfanctant, whereas in the case of the other drugs examined an increase occurred. The interpretation of the process for drotaverine and "RJ-64" needs further experimental clarification. The importance of kinetic concepts in pharmaceutical technology is emphasized.