Figure 6: ChEI enhances ACh and enhanced ACh compensates for other AA inserts besides ACh downregulation. We prescribe three main ChEIs—donepezil, galantamine, and rivastigmine—to patients with mild or moderate stage AD. For donepezil, 5 mg doses are allowed in Japan (a). Of these ChEIs (including generic medicines), only Aricept is permitted for LBD patients in Japan (since September 2014). In general, the dose of Aricept is 10 mg for LBD (10 mg of donepezil is permitted only for severe AD patients in Japan) (b). We believe that the difference in required dosage between AD and LBD is because there is no other AA insert in AD besides ACh downregulation. However, another AA insert (e.g., HPA axis hyperactivity) is present in LBD, so it is important to upregulate ACh to compensate for this AA insert. AA: anticholinergic activity, ACh: acetylcholine, AD: Alzheimer’s disease, ChEI: cholinesterase inhibitor, HPA axis: hypothalamic-pituitary-adrenal axis, and LBD: Lewy body disease. 5 mg (in (a)): 5 mg doses of donepezil; 10 mg (in (b)): 10 mg doses of Aricept (donepezil). This figure is reproduced from Konishi et al. [24] with the permission of Karger Publishers, Basel, Switzerland.