Anemia or anaemia is usually defined as a decrease in the amount of red blood cells
Anemia or anaemia is usually defined as a decrease in the amount of red blood cells (RBCs) or the amount of hemoglobin in the blood.
It can also be defined as a lowered ability of the blood to carry oxygen.When anemia comes on slowly the symptoms are often vague and may include: feeling tired, weakness, shortness of breath or a poor ability to exercise. Anemia that comes on quickly often has greater symptoms which may include: confusion, feeling like one is going to pass out, and an increased desire to drink fluids.
There needs to be significant anemia before a person becomes noticeably pale. There may be additional symptoms depending on the underlying cause.