A WBC count in the range of 4000 to 4700 cells/mcL is technically at the lower limit of normal, but if it has remained stable since 2014, it is likely your baseline (constitutional) level rather than an acute disease. While you feel this 'borderline low' count is causing your frequent colds and drowsiness, it is often the other way around—chronic low-grade inflammation or underlying nutritional deficiencies (like
B12 or Folate) can keep the WBC count at the lower end while causing systemic fatigue
Next Steps
But need your whole blood report so can ruke our the causes and plan the treatment accordingly
for this you connect with me and consult