What is fatigue? What may contribute to fatigue?

What is fatigue?

Fatigue as a symptom of cancer or side effect of treatment goes well beyond simply feeling temporarily tired or worn out, such as from a sleepless night. It is “unexplained, persistent, and relapsing exhaustion,”1How Tired Is Too Tired? Web MD. April 21, 2021. Viewed May 11, 2022. and it “lasts longer, is more profound and isn’t relieved by rest.”2Mayo Clinic staff. Fatigue. Mayo Clinic. December 2, 2020. Viewed May 11, 2022.

Caregivers can also experience fatigue. Caregiver fatigue occurs when the caregiver feels physically, emotionally, and physically exhausted, often leading to a change in attitude. Neglecting your mental and physical health and allowing long-term stress to linger can result in caregiver burnout.3Stringfellow A. What is Caregiver Fatigue? Seniorlink Blog. March 11, 2019. Viewed May 17, 2022. Caregivers often give priority to the health and well-being of their loved one needing care, forgetting to care for themselves. Preventing fatigue or addressing it when it first arises with good self care is essential for the well-being of both you and your loved one.

What are the signs or symptoms of fatigue? 

Warning signs of impending cancer-related fatigue:4Cancer Fatigue. Cleveland Clinic. September 8, 2021. Viewed May 24, 2022.

Tired eyes

Tired legs

Whole body tiredness

Stiff shoulders

Decreased energy or lack of energy

Inability to concentrate

Weakness or malaise

Boredom or lack of motivation


Increased irritability

Nervousness, anxiety or impatience

Symptoms of fatigue

From the Moffitt Cancer Center5Cancer-Related Fatigue. Moffitt Cancer Center. July 15, 2015. Viewed May 24, 2022.

Chronic tiredness or sleepiness unrelieved by a good night’s sleep

Feeling tired even after having slept

No energy to perform regular activities

Difficulty concentrating or remembering things

Feeling negative, irritable, impatient, or unmotivated

Lacking interest in everyday activities

Less than your usual attention to your personal appearance

Sleeping more or spending more time in bed

Symptoms associated with caregiver fatigue

From the Seniorlink Blog6Stringfellow A. What is Caregiver Fatigue? Seniorlink Blog. March 11, 2019. Viewed May 24, 2022.

Feeling overwhelmed and constantly worried 

Feeling tired often

Withdrawal from friends and family members

Lack of motivation for caregiving and for trying new things

Losing interest in things you used to enjoy

Excessive alcohol or drug use, including sleeping pills

Having frequent headaches, bodily pain or other physical symptoms

Missing doctor’s appointments and other responsibilities

Being unable to fall and stay asleep or sleeping too much 

Feeling angry

Feeling sad or depressed—hopelessness, alienation, helplessness, irritability

Resentment toward the person you care for, possibly leading to anger

What may contribute to fatigue?

These situations may trigger or worsen fatigue among people with cancer:

  • Alcohol or drug use
  • Excess physical activity
  • Lack of physical activity
  • Medications, such as antihistamines, cough medicines, or sedatives
  • Not enough sleep
  • Unhealthy eating habits
  • Consuming excess caffeine
  • Metabolic or hormone imbalances
  • Infection
  • Changes in gut microbes

Pain may worsen fatigue.7Charalambous A, Giannakopoulou M, Bozas E, Paikousis L. Parallel and serial mediation analysis between pain, anxiety, depression, fatigue and nausea, vomiting and retching within a randomised controlled trial in patients with breast and prostate cancer. BMJ Open. 2019 Jan 24;9(1):e026809. Inflammation, which can also lead to pain, is also independently linked to fatigue.8Wang A, Ling Z et al. Gut microbial dysbiosis may predict diarrhea and fatigue in patients undergoing pelvic cancer radiotherapy: a pilot study. PLoS One. 2015 May 8;10(5):e0126312. Alleviating either fatigue or pain to interrupt the feedback loop between them may provide relief of both symptoms.

Medications and therapies

Some medications used during cancer treatment or for other conditions may trigger fatigue. Check the inserts with any prescription medications you use or ask your pharmacist if you have concerns.

Some cancer treatments can cause fatigue, such as radiation therapy, surgery, and some drugs, hormone therapies, and immunotherapies.

Drowsiness is a side effect of aspirin or other nonsteroidal anti-inflammatory drugs (NSAIDs) and many other prescription medications.

Some complementaryin cancer care, complementary care involves the use of therapies intended to enhance or add to standard conventional treatments; examples include supplements, mind-body approaches such as yoga or psychosocial therapy, and acupuncture therapies may contribute to fatigue:

  • Fatigue or lack of energy (lethargy) is a side effect of cannabis; strong evidence shows higher risks of sleepiness or drowsiness among people using cannabis › 
  • Fatigue is a side effect of copper chelation › 
  • Lack of energy (lethargy) or fatigue is a side effect of a ketogenic diet ›

Other therapies that may contribute to short-term fatigue:

Risk factors for fatigue

In addition to cancer and treatment-related risk factors, people with these conditions are at higher risk of fatigue:

Overweight or obesity


Heart disease

Mental health issues, such as depression or anxiety

Sleep problems


  • Cancer
  • Rheumatology illnesses such as rheumatoid arthritis and systemic lupus
  • Fibromyalgia
  • Chronic fatigue syndrome

Caregiver fatigue

Risk factors for caregiver fatigue:9Mayo Clinic staff: Caregiver stress: tips for taking care of yourself. Mayo Clinic. March 22, 2022. Viewed May 24, 2022.

Being female

Having fewer years of formal education

Living with the person you are caring for

Social isolation

Having depression

Financial difficulties

Higher number of hours spent caregiving

Lack of coping skills and difficulty solving problems

Lack of choice in being a caregiver

Situations that may trigger or worsen caregiver fatigue:10Stringfellow A. What is Caregiver Fatigue? Seniorlink Blog. March 11, 2019. Viewed May 24, 2022. 

Role strain, feeling overwhelmed and unable to perform a caregiver role to the best of your ability

Unreasonable demands from your care recipient, other family members, work, or other sources)

Unrealistic expectations

Lack of control including lack of resources for caregiving, such as time or money

Poor health


Nancy Hepp, MS

Lead Researcher
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Ms. Hepp is a researcher and communicator who has been writing and editing educational content on varied health topics for more than 20 years. She serves as lead researcher and writer for CancerChoices and also served as the first program manager. Her graduate work in research and cognitive psychology, her master’s degree in instructional design, and her certificate in web design have all guided her in writing and presenting information for a wide variety of audiences and uses. Nancy’s service as faculty development coordinator in the Department of Family Medicine at Wright State University also provided experience in medical research, plus insights into medical education and medical care from the professional’s perspective.

Nancy Hepp, MS Lead Researcher

Laura Pole, MSN, RN, OCNS

Senior Clinical Consultant
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Laura Pole is senior clinical consultant for CancerChoices. Laura is an oncology clinical nurse specialist who has been providing integrative oncology clinical care, navigation, consultation, and education services for over 40 years. She is the co-creator and co-coordinator of the Integrative Oncology Navigation Training at Smith Center for Healing and the Arts in Washington, DC. Laura also manages the “Media Watch Cancer News That You Can Use” listserv for Smith Center/Commonweal. In her role as a palliative care educator and consultant, Laura has served as statewide Respecting Choices Faculty for the Virginia POST (Physician Orders for Scope of Treatment) Collaborative as well as provided statewide professional education on palliative and end-of-life care for the Virginia Association for Hospices and Palliative Care.

For CancerChoices, Laura curates content and research, networks with clinical and organizational partners, brings awareness and education of integrative oncology at professional and patient conferences and programs, and translates research into information relevant to the patient experience as well as clinical practice.

Laura sees her work with CancerChoices as a perfect alignment of all her passions, knowledge and skills in integrative oncology care. She is honored to serve you.

Laura Pole, MSN, RN, OCNS Senior Clinical Consultant

Last update: May 21, 2024

Last full literature review: April 2022

CancerChoices provides information about integrativein cancer care, a patient-centered approach combining the best of conventional care, self care, and evidence-informed complementary care in an integrated plan cancer care. We review complementaryin cancer care, complementary care involves the use of therapies intended to enhance or add to standard conventional treatments; examples include supplements, mind-body approaches such as yoga or psychosocialtherapy, and acupuncture therapies and self carelifestyle actions and behaviors that may impact cancer outcomes; examples include eating health-promoting foods, limiting alcohol, increasing physical activity, and managing stress practices to help patients and professionals explore and integrate the best combination of conventionalthe cancer care offered by conventionally trained physicians and most hospitals; examples are chemotherapy, surgery, and radiotherapy and complementary therapies and practices for each person.

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