Below are conditions that are often present with fatigue and therefore should be checked. Managing these conditions can greatly help reduce the fatigue. These conditions are:
emotional distress (including depression and anxiety)
decreased activity level
other medical conditions (such as low thyroid gland function, infections, and heart, lung, kidney, or nervous system disease).
Fatigue is different for every cancer patient. Although many treatment-related and disease-related factors may contribute to being fatigued, exactly what causes cancer-related fatigue is still unknown.