If you are suffering from persistent fatigue that cannot be explained by other factors, you may have diabetes, which is a condition in which high levels of sugar are not broken down and converted into energy.
In short, although the body has the necessary fuel, it cannot use it and runs out of energy.
A different lifestyle, diet, exercise, and especially insulin therapy will bring the body back to processing sugars.
Memory loss from drugs
Tranquilizers, prescribed to reduce anxiety and agitation, or even drugs such as sleeping pills can act on memory by reducing it, but they are not the only ones since antihypertensive