We determined 293 plasma-ACTH levels out of 49 patients. In 12 patients with various pituitary diseases 168 samples were collected during a standardized pituitary stimulation test. For this purpose we used the following kits: the DYNOtest ACTH and LUMItest ACTH and Allegro HS-ACTH test. Additionally, morning ACTH levels were analyzed from 49 patients using Allegro HS ACTH test and DYNOtest ACTH. Regarding ACTH concentrations during pituitary stimulation the clinical usefulness of the 3 named tests were comparable. Pair differences of morning ACTH levels were not statistically significant. In a setting of a wide range of ACTH levels all 3 trials proved appropriate for making a diagnosis. Practicability of all 3 tests was similar. For all 3 methods incubation can be done overnight which saves time. Reagents can be reused when frozen immediately after reconstitution.