The potential of these three Amaryllidoideae genera against Alzheimer’s disease was then evaluated by measuring their AChE and BuChE inhibitory activity, revealing that C. incarnatus and U. formosa (from Sucumbíos province) showed the best results with IC50 values of 1.73 ± 0.25 and 30.56 ± 1.56 μg·mL−1, respectively. This evidence concerns the gene ACHE and early-onset autosomal dominant Alzheimer disease.