To check overall health, to diagnose a medical condition, to monitor a medical condition.

Clinical Significance

A hemoglobin test for several reasons-

To check overall health.  doctor may test hemoglobin as part of a complete blood count during a routine medical examination to monitor general health and to screen for a variety of disorders, such as anemia.

To diagnose a medical condition.  doctor may suggest a hemoglobin test if 're experiencing weakness, fatigue, shortness of breath or dizziness. These signs and symptoms may point to anemia or polycythemia vera. A hemoglobin test may help diagnose these or other medical conditions.

To monitor a medical condition. If 've been diagnosed with anemia or polycythemia vera, doctor may use a hemoglobin test to monitor condition and guide treatment.

Healthy ranges for children vary with age and sex. The range for a healthy hemoglobin level may differ slightly from one medical practice to another.

Lower than normal results

If hemoglobin level is lower than normal, have anemia. There are many forms of anemia, each with different causes, which can include-

• Iron deficiency
• Vitamin B-12 deficiency
• Folate deficiency
• Bleeding
• Cancers that affect the bone marrow, such as leukaemia
• Kidney disease
• Liver disease
• Hypothyroidism

Thalassemia — a genetic disorder that causes low levels of hemoglobin and red blood cells

If 've been previously diagnosed with anemia, a hemoglobin level that's lower than normal may indicate a need to alter treatment plan.

Higher than normal results

If hemoglobin level is higher than normal, it may be the result of-

• Polycythemia vera - a blood disorder in which bone marrow makes too many red blood cells
• Lung disease
• Dehydration
• Living at a high altitude
• Heavy smoking
• Burns
• Excessive vomiting
• Extreme physical exercise

If 've been previously diagnosed with polycythemia vera, an elevated hemoglobin level may indicate a need to alter treatment plan.

If hemoglobin level is below or above normal, doctor may want to evaluate the hemoglobin test results along with those of other tests, or additional tests may be necessary, to determine next steps.