Kornhuber worked in the Department of Psychiatry at the University of Würzburg, Germany, as Postdoctoral Fellow, Resident and Supervising Physician.

In 1996 he obtained an appointment to a full professorship in the Department of Psychiatry at the University of Göttingen, Germany, where he was Chairman of the Gerontopsychiatric Section.

Kornhuber described novel molecular mechanisms of approved psychotropic drugs, namely that memantine, amantadine, budipine and orphenadrine act as low-affinity NMDA-receptor antagonists.

[1][2] The data obtained with memantine formed an important basis for its worldwide approval as an antidementive drug.

[3] Furthermore, he found that antidepressant drugs like amitriptyline and fluoxetine mediate their effects on neurogenesis and behavior by lowering ceramide abundance in the brain.