Fatigue and dizziness are symptoms that can be related to many medical conditions, such as treatment for cancer, substance abuse, alcoholism, altitude sickness, or strict dieting. Health care providers rely on a comprehensive health history to provide information such as age, other symptoms such as pain, family history, dietary practices and a list of current medications that may explain why the patient is tired and dizzy. Routine vital signs, a thorough physical exam and laboratory tests can help form a complete picture and narrow down a diagnosis.
In a female of childbearing age, the most common cause of fatigue and dizziness is early pregnancy. Even before pregnancy tests are positive, hormone changes occur that shunt blood away from the muscles and brain and increase the heart's workload similar to that of an aerobic workout. According to the Mayo Clinic, a woman can compensate for these changes in her body by snacking on high protein foods, avoiding standing for long periods, and getting up slowly when lying down or sitting.
Hemoglobin is a component of red blood cells that carry oxygen from the lungs to the heart. where it is distributed to other parts of the body. A drop in hemoglobin reduces oxygen stores and can result in fatigue, dizziness and, in severe cases, shortness of breath. Iron deficiency is a common cause, but a lack of other nutrients such as folate or vitamin B12 may also create anemia. Other types listed by the University of Maryland Medical Center include pernicious anemia, hemolytic anemia and sickle cell anemia, all of which respond to different treatments .
Low Blood Pressure
The American Heart Association asserts that blood pressure under 120/80 is considered normal. Chronically low blood pressure, such as 85/55, is not considered a problem unless it causes symptoms of dizziness, fatigue, nausea, clammy skin, confusion or blurred vision. Low blood pressure can be caused by heart failure, hypothyroidism, low blood sugar or dehydration. Medications used to treat high blood pressure may cause fatigue and dizziness, especially in the beginning. Other drugs that may lower blood pressure are diuretics, pain killers, antidepressants, drugs used to treat erectile dysfunction and nitroglycerine.
Chronic Fatigue Syndrome
Chronic fatigue syndrome (CFS) is characterized by tiredness that persists longer than six months despite adequate rest. Impaired concentration, joint, muscle, and headaches and sore throat are other symptoms associated with CFS, but the range and severity of symptoms vary among individuals. There are no tests for CFS; diagnosis is made by ruling out other possible causes such as cancer, depression, multiple sclerosis, lupus, mononucleosis and fibromyalgia. The Centers for Disease Control and Prevention report that more than one million people in the United States are diagnosed with CFS. 20 to 50 percent report other symptoms, including dizziness.