Absorption and distribution of ibuprofen from a cream formulation after dermal administration to guinea pigs

Objective of this experimental study is the investigation of the absorption and distribution of ibuprofen in skin and muscle tissue in guinea pigs after dermal administration of Dolgit Creme. After administration of the test substance the following blood sampling intervals were applied: 10, 20, 40, 60, 90 and 120 min. Skin and muscle tissue of the application area were also sampled at the same time intervals. In blood and plasma only 90 and 120 min after administration of the test substance concentrations of radioactivity were found which were above the limit of detection. In the skin of the application area most of the radioactivity applied was found. High concentrations of radioactivity were found in the hair follicles. In muscle tissue below the application area, dependent on the depth, concentrations between 228 micrograms and 13 micrograms of parent compound/g (tissue) were found. This indicates that after dermal administration of ibuprofen cream therapeutically relevant levels were reached even in deeper tissue.