A review of neurochemical research on classical neurotransmitters, i.e. acetylcholine, serotonin, noradrenaline, dopamine, glutamate, and GABA in Alzheimer's disease is presented. Findings are linked to the information processing system of the human brain to establish a more functional neurochemistry. On this basis, different pharmacotherapeutic strategies are discussed. Our conclusion is that current symptomatic therapy of Alzheimer's disease is insufficient. Besides therapy with acetylcholinesterase inhibitors, comedication to act on imbalances between serotonin and noradrenaline on the one site, and dopamine, glutamate and GABA on the other site should should be considered.