Fatigue
Tiredness; Weariness; Exhaustion; Lethargy
Fatigue is a feeling of weariness, tiredness, or lack of energy.
Do you feel tired and listless? Do you find your mind drifting during the day? Do you get dizzy or short of breath whenever you climb the stairs? There are a few possible reasons for the way you feel, but you could have anemia. You could even have anemia without noticing any symptoms at all. Anemia is a problem with hemoglobin, a substance in red blood cells that carries oxygen throughout your body. Without enough hemoglobin, your heart and other organs can't get the oxygen they need to work. When your organs slow down, you slow down and you start feeling tired and listless. Many different health conditions can cause anemia, from heavy blood loss during a woman's period, to pregnancy, to an underactive thyroid gland. Healthy red blood cells are made in your bone marrow, the soft tissue in the middle of your bones. Any disease that damages blood marrow, such as lymphoma or leukemia, can also affect your red blood cell production. Anemia can also be caused by an immune system problem that damages red blood cells, or surgery to the stomach or intestines. How do you know if you have anemia? You may feel tired, dizzy, and have trouble concentrating. You may get sick more often. People with anemia often complain of chest pain, headaches, or shortness of breath. Your skin might look pale, like you haven't seen the sun for months. Because these can also be symptoms of other conditions, your doctor will confirm that you have anemia by taking a blood test to check your red blood cell count and hemoglobin level. Blood tests can also look for problems that may be causing your anemia, such as a vitamin or iron deficiency. If you are anemic, it's very important to treat it. When your body isn't getting enough oxygen, it can starve vital organs like your heart. This can lead to a heart attack. How you treat anemia really depends on the cause. If the problem is with your bone marrow, you may take a medicine called erythropoietin, which will help your bone marrow make more red blood cells. If the problem is a vitamin or mineral deficiency, your doctor may prescribe iron, vitamin B12, or folic acid supplements. Or, you may need a blood transfusion to replace damaged red blood cells with healthy ones. How well you do really depends on what's causing your anemia. Call your doctor if you have any symptoms like fatigue or shortness of breath. Once your doctor can find and treat the cause of your anemia, you should have more energy and start feeling like your old self again.
You tuck yourself under the covers, turn out the light, and look forward to eight hours of blissful slumber. But, after turning for hours you're still exhausted, and no closer to sleep than when you first got into bed. Let's talk today about sleep disorders. Sleep disorders fall into four basic categories. The scenario I described, in which you toss and turn because you can't fall asleep, is called insomnia. Another type of insomnia is when you wake up in the middle of the night and can't get back to sleep. Sometimes people get insomnia for a night or two because they're stressed out over a big meeting at work, or they're excited about an upcoming trip. Others can't sleep night after night, and that's called chronic insomnia. People with the second category of sleep disorders have a hard time staying awake during the day, even if they slept well the night before. This is called hypersomnia. Sometimes doctors can't find a cause for hypersomnia. But in many cases, a health condition like fibromyalgia, a thyroid problem, a disease like mononucleosis, obesity, or obstructive sleep apnea, can make you sleepy. If you notice a co-worker is nodding off in the middle of meetings, he might have narcolepsy, a sleep disorder that causes people to sleep uncontrollably at inappropriate times during the day. Narcolepsy isn't only embarrassing, it can be dangerous if you nod off behind the wheel of a car. A sleep rhythm problem means that you can't stick to a normal sleep schedule. Maybe you work the night shift at your job, or you're always traveling to different time zones and are constantly battling jet lag. Well, whatever the cause, the lack of a normal sleep pattern is called a sleep rhythm disorder. And finally, there are the types of sleep disorders that wake you up with a jolt in the middle of the night, and, these are called parasomnias, and they can severely interrupt your sleep. You may walk in your sleep, or act out your dreams. Children often have night terrors, in which they wake up from a deep sleep in a terrified state. The good news is that you don't have to live on fewer hours of sleep, because there are decent treatments for sleep disorders. If you're struggling to sleep throughout the night, and dragging through the day as a result, talk to your doctor, who can refer you to a sleep specialist for an evaluation.
Considerations
Fatigue is different from drowsiness. Drowsiness is feeling the need to sleep. Fatigue is a lack of energy and motivation. Drowsiness and apathy (a feeling of not caring about what happens) can be symptoms that go along with fatigue.
Fatigue can be a normal and important response to physical activity, emotional stress, boredom, or lack of sleep. Fatigue is a common symptom, and it is usually not due to a serious disease. But it can be a sign of a more serious mental or physical condition. When fatigue is not relieved by enough sleep, good nutrition, or a low-stress environment, it should be evaluated by your health care provider.
Causes
There are many possible causes of fatigue, including:
- Anemia (including iron deficiency anemia)
- Depression or grief
- Iron deficiency (without anemia)
- Medicines, such as sedatives or antidepressants
- Persistent pain
- Sleep disorders such as insomnia, obstructive sleep apnea, or narcolepsy
- Thyroid gland that is underactive or overactive
- Use of alcohol or drugs, such as cocaine or narcotics, especially with regular use
Fatigue can also occur with the following illnesses:
- Addison disease (a disorder that occurs when the adrenal glands don't produce enough hormones)
- Anorexia or other eating disorders
- Arthritis, mainly adult or juvenile rheumatoid arthritis
- Autoimmune diseases such as systemic lupus erythematosus
- Cancer
- COVID-19
- Diabetes
- Fibromyalgia
- Heart failure
- Infection, especially one that takes a long time to recover from or treat, such as bacterial endocarditis (infection of the heart muscle or valves), parasitic infections, hepatitis, HIV/AIDS, tuberculosis, and mononucleosis
- Kidney disease
- Liver disease
- Malnutrition
Certain medicines may also cause drowsiness or fatigue, including antihistamines for allergies, blood pressure medicines, sleeping pills, steroids, and diuretics (water pills).
Chronic fatigue syndrome (CFS) is a condition in which symptoms of fatigue persist for at least 6 months and do not resolve with rest. The fatigue may be worsened with physical activity or mental stress. It is diagnosed based on the presence of a specific group of symptoms and after all other possible causes of fatigue are ruled out.
Home Care
Here are some tips for reducing fatigue:
- Get enough sleep each night.
- Make sure your diet is healthy and well-balanced, and drink plenty of water throughout the day.
- Exercise regularly.
- Learn better ways to relax. Try yoga or meditation.
- Maintain a reasonable work and personal schedule.
- Change or reduce your stressors, if possible. For example, if you are able, take a vacation or resolve relationship problems.
- Discuss with your provider whether any supplemental vitamins might help you.
- Avoid alcohol, nicotine, and drug use.
If you have long-term (chronic) pain or depression, treating it often helps the fatigue. Be aware that some antidepressant medicines may cause or worsen fatigue. If your medicnie is one of these, your provider may have to adjust the dosage or switch you to another medicine. DO NOT stop or change any medicines without first talking to your provider.
Stimulants (including caffeine) are not effective treatments for fatigue. They can make the problem worse when they are stopped. Sedatives also tend to worsen fatigue.
When to Contact a Medical Professional
Contact your provider right away if you have any of the following:
- Confusion or dizziness
- Blurred vision
- Little or no urine output
- Recent swelling and weight gain
- Thoughts of harming yourself or of suicide
Contact your provider for an appointment if you have any of the following:
- Unexplained weakness or fatigue, especially if you also have a fever, unintentional weight loss, or regular sweats
- Constipation, dry skin, weight gain, or you cannot tolerate cold
- Wake up and fall back to sleep many times during the night
- Frequent headaches
- Are taking medicines, prescribed or non-prescribed, or using drugs that may cause fatigue or drowsiness
- Feel sad or depressed
- Insomnia
What to Expect at Your Office Visit
You will be asked about your medical history, fatigue symptoms, and your lifestyle, habits, and feelings.
Your provider will likely perform a complete physical examination, paying special attention to your heart, lymph nodes, thyroid, abdomen, and nervous system.
Tests that may be ordered include the following:
- Blood tests to check for anemia, diabetes, inflammatory diseases, and possible infection
- Kidney function tests
- Liver function tests
- Thyroid function tests
- Urinalysis
Treatment depends on the cause of your fatigue symptoms.
References
Clauw DJ. Fibromyalgia. In: Goldman L, Cooney KA, eds. Goldman-Cecil Medicine. 27th ed. Philadelphia, PA: Elsevier; 2024:chap 253.
Regehr J. Fatigue. In: Kellerman RD, Rakel DP, Heidelbaugh JJ, Lee EM, eds. Conn's Current Therapy 2023. Philadelphia, PA: Elsevier 2023:14-15.
Seller RH, Symons AB. Fatigue. In: Seller RH, Symons AB, eds. Differential Diagnosis of Common Complaints. 7th ed. Philadelphia, PA: Elsevier; 2018:chap 14.
Version Info
Last reviewed on: 6/12/2023
Reviewed by: Jacob Berman, MD, MPH, Clinical Assistant Professor of Medicine, Division of General Internal Medicine, University of Washington School of Medicine, Seattle, WA. Also reviewed by David C. Dugdale, MD, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.
