MAPT and Alzheimer disease: This study summarized the historical basic research on Shen Zhi Ling oral liquid treatment of AD and revealed the following main mechanisms: (1) inhibition of the excessive deposition of amyloid protein and phosphorylation of tau protein; (2) regulation of multiple neurotransmitters; (3) improving energy metabolism; and (4) improving the expression of autophagy-related proteins and learning-memory-associated proteins.