When lethargy develops as a response to various life situations, it often resolves with rest, increased sleep, good nutrition, and being active. However, in the case of illness, lethargy can linger for days, weeks, or even months.
This article discusses the symptoms and potential causes of lethargy. It also covers treatment options and information on when to contact your healthcare provider.
Symptoms of Lethargy
Lethargy has been described as unrelenting exhaustion that includes chronic fatigue, lack of energy, and sluggishness. People who are lethargic may also experience:
DepressionApathy (lack of interest in or enthusiasm for things)Lack of motivationFeeling less alertCognitive difficulties (forgetfulness and trouble concentrating)Severe drowsiness
Other symptoms that may accompany lethargy include:
Aches and pains that won’t go away despite treatmentSleep problemsSensitivity to hot and cold temperaturesEye inflammationChronic fatigue lasting more than two weeksSwollen neck glandsUnexplained weight changesFeeling sad, empty, or irritable
People who are lethargic may act as if they are in a daze. They may not move as quickly as they usually do and may be aware that they are in poor health.
Causes of Lethargy
Lethargy has a number of possible causes. It can be the body’s response to not getting enough sleep, overexertion, stress, lack of activity, or improper nutrition. It can also be a side effect of medication or the body’s response to alcohol. Consumption of alcohol while on medication can also cause a person to feel lethargic.
Lethargy is a symptom of many acute (abrupt onset) conditions, including the flu, stomach viruses, fever, dehydration, and nutritional deficiencies. Other serious medical conditions that cause lethargy include, but are not limited to:
Adrenal problems Anemia Autoimmune disorders Cancer Chronic fatigue syndrome Depression Fibromyalgia Hyperthyroidism Hypothyroidism Hydrocephalus (brain swelling) or brain injuries Kidney failure Meningitis Pituitary diseases
How to Treat Lethargy
If lethargy is caused by emotional or physical stress or exhaustion, it may not require medical treatment. It is often resolved by getting enough sleep, maintaining a healthy diet, and managing stress.
When lethargy is determined to be caused by an underlying cause, treatment is aimed at the cause. Here are possible treatments for lethargy, listed by the cause:
Dehydration: Treatment includes intravenous fluids and/or electrolyte consumption. Hypothyroidism: Treatment may include thyroid replacement hormone, such as levothyroxine. Autoimmune diseases: Treatment may include relieving inflammation with disease-modifying antir-rheumatic drugs (DMARDs), nonsteroidal anti-inflammatory drugs (NSAIDs), and corticosteroids. Depression: This can be treated by managing depressive symptoms with psychotherapy and/or antidepressant medications, such as Zoloft (sertraline) and Lexapro (escitalopram). Cancer-associated lethargy: Healthcare providers may prescribe stimulant medications, such as Provigil (modafinil) for short periods to boost energy and increase wakefulness.
Are There Tests to Diagnose Lethargy?
The first step in determining the cause of lethargy is to see a practitioner. Your healthcare provider will take a medical history, ask you about your symptoms, and perform a physical exam. They may also do tests, including:
Blood tests to check for anemia, diabetes, inflammatory diseases, and possible infectionKidney function testsLiver function testsThyroid function testsUrinalysis
Your healthcare provider may also recommend seeing a specialist if the cause of lethargy and other symptoms cannot be established.
When to See a Healthcare Provider
Lethargy is rarely a medical emergency. However, it can become one if it is accompanied by other serious symptoms. It is important to seek immediate medical attention or call 911 for the following, which may be signs of a medical emergency:
Abdominal painAltered consciousnessBlurred visionChest painConfusionFacial paralysisHigh feverInability to move arms and legsNausea and vomitingRapid heart rateSevere dizzinessSevere headacheSevere painShortness of breathSignificant changes in behavior (including thoughts of self-harm)Slurred speechSudden and severe swellingSudden energy loss
Summary
Lethargy involves more than being tired, sleepy, or drowsy. It is a state of being exhausted, with little to no energy, and it tends to linger. In some cases, lethargy may be due to certain life situations and lifestyle habits, but it can also be a symptom of certain diseases and health conditions. Treatment depends on the underlying cause.
Difficulty with waking or appearing to be in a daze, especially when accompanied by fevers higher than 102 degrees FWeaknessDehydration (including reduced tears, dry mouth, and decreased urine output)RashesVomiting
A Word From Verywell
It can be challenging to nail down a cause for ongoing lethargy. Once the cause of lethargy is determined, it is important to follow the treatment plan prescribed by your healthcare provider to feel better and reduce your risk for any potential complications.
