HTR5A and Alzheimer disease: Ongoing clinical trials evaluating the efficacy of 5‐HT agonists suggest that enhancing the 5‐HT signaling by 5‐HT agonists may improve the behavioral symptoms of AD patients [96] (Table 2).On the other hand, 5‐HT antagonists which block the action of 5‐HT at specific receptors (like 5‐HT2A and 5‐HT7) can alleviate psychotic symptoms and improve mood stability in AD patients by reducing neuroinflammation associated with AD pathology [97].