©2018 WebMD, Inc. All rights reserved. eMedicineHealth does not provide medical advice, diagnosis or treatment. See Additional Information.

Symptoms and Signs of Hemoglobin Test: Normal, High, Low Levels

Doctor's Notes on Hemoglobin

Hemoglobin is an oxygen-carrying protein found inside of red blood cells (known as erythrocytes). The hemoglobin molecule is made up of four protein chains joined together and plays a role in maintaining the shape of the red blood cells. Anemia is a medical condition in which the red blood cell count or level of hemoglobin is lower than normal. Anemia can arise dur to loss of red blood cells (such as bleeding), decreased production of red blood cells by the bone marrow, or destruction of red blood cells.

Symptoms of anemia are related to lower amounts of oxygen delivered to the body. They can include malaise, fatigue, shortness of breath, heart palpitations, and hair loss. The skin may appear pale in people with anemia. Other associated symptoms can include dizziness and heart problems.

Medical Author:
Medically Reviewed on 3/11/2019


Kasper, D.L., et al., eds. Harrison's Principles of Internal Medicine, 19th Ed. United States: McGraw-Hill Education, 2015.