Definition

Nearly everyone is overtired or overworked from time to time. Such instances of temporary fatigue usually have an identifiable cause and a likely remedy.

Unrelenting exhaustion, on the other hand, lasts longer, is more profound and isn't relieved by rest. It's a nearly constant state of weariness that develops over time and reduces your energy, motivation and concentration. Fatigue at this level impacts your emotional and psychological well-being, too.

Causes

Most of the time fatigue can be traced to one or more of your habits or routines, particularly lack of exercise. It's also commonly related to depression. On occasion, fatigue is a symptom of other underlying conditions that require medical treatment.

Lifestyle factors

Taking an honest inventory of things that might be responsible for your fatigue is often the first step toward relief. Fatigue may be related to:

• Alcohol or drug use
• Excess physical activity
• Jet lag disorder
• Lack of physical activity
• Medications, such as antihistamines, cough medicines
• Not enough sleep
• Unhealthy eating habits

Conditions

Unrelenting exhaustion may be a sign of a condition or an effect of the drugs or therapies used to treat it, such as:

• Acute liver failure
• Anemia
• Anxiety disorders
• Cancer
• Chronic fatigue syndrome
• Chronic infection or inflammation
• Chronic kidney disease
• Concussion
• COPD (chronic obstructive pulmonary disease) exacerbation — worsening of symptoms
• Coronavirus disease 2019 (COVID-19)
• Depression (major depressive disorder)
• Diabetes
• Emphysema
• Fibromyalgia
• Grief
• Heart disease
• Hyperthyroidism (overactive thyroid)
• Hypothyroidism (underactive thyroid)
• Inflammatory bowel disease (IBD)
• Medications and treatments, such as chemotherapy, radiation therapy, pain drugs, heart drugs and antidepressants
• Multiple sclerosis
• Obesity
• Pain that's persistent
• Sleep apnea
• Stress
• Traumatic brain injury

When to see a doctor

Call 911 or your local emergency number

Get emergency help if your fatigue is related to a mental health problem and your symptoms also include:

• Thoughts of harming yourself or of suicide
• Concern that you may harm someone else

Also get emergency care if your fatigue is accompanied by any of the following:

• Chest pain
• Shortness of breath
• Irregular or fast heartbeat
• Feeling that you might pass out
• Severe abdominal, pelvic or back pain

Seek immediate medical attention

Get someone to take you to an emergency room or urgent care if fatigue is accompanied by:

• Abnormal bleeding, including bleeding from your rectum or vomiting blood
• Severe headache

Schedule a doctor's visit

Call for an appointment with your doctor if your fatigue has persisted for two or more weeks despite making an effort to rest, reduce stress, choose a healthy diet and drink plenty of fluids.