What is asthenia?

Asthenia is the loss or lack of bodily strength also referred to as generalized weakness.

Persons undergoing chemotherapy treatments can have weakness for a variety of reasons both physical and mental. Causes of weakness may include:

  • Cancer treatments; chemotherapy, biologic response modifiers, radiation therapy.
  • Side effects of treatment.
  • Anemia, (low red blood cell count).
  • Decreased mobility, spending a lot of time in bed (muscles tend to weaken).
  • Overexertion
  • Poor nutrition, dehydration.
  • Sleeplessness.
  • Stress
  • Uncontrolled pain.
  • Depression.
  • Endocrine diseases of metabolism, such as of the thyroid gland, may cause fatigue and weakness.

What are some symptoms of weakness to look for?

  • Your symptoms will vary depending on the cause of your weakness.
  • Tiredness.
  • Muscle aches and pains.
  • Difficulty changing positions; from sitting to standing.
  • Dizziness and imbalance.
  • Shortness of breath.
  • Fever and/or chills (signs of infection)
  • Depression

Things you can do about asthenia:

Notify your health care professional if noticing any of the weakness symptoms described above so evaluation can occur.


  • With moderate imbalance, walk slowly and often. Walk with assistance if you are having severe dizzy episodes, weakness, or imbalance.
  • If you are at risk for falling down due to weakness or imbalance:
  • Remove throw rugs from your usual walking path in your home if you are at risk for falling down. Avoid clutter, if possible.
  • Place track lighting, or keep the areas that you spend the most time in, well lit. this will prevent your chance of falling, if you are able to see more clearly.
  • If you are at risk for falling down due weakness or unsteady movements, and you live or spend most of the day alone, try to carry a cordless phone, or another device to notify someone if you fall down.
  • Wear well-fitting shoes. Make sure the shoelaces or Velcro straps are tied tightly.
  • Do not operate any heavy machinery. It is also important to be careful when taking new medications.
  • Use any braces, canes, walker or other supportive devices prescribed by your health care professional.

Other therapies:

  • Physical therapy (PT): May be recommended or requested to evaluate for safety concerns, optimize mobility and for assistance with other interventions as appropriate such as exercise for muscle strengthening or assistive devices.
  • Occupational therapy (OT): If you are experiencing imbalance or problems with mobility, in general, you may be taught in OT how to do many tasks that you normally do, in a more effective manner.

To help prevent problems related to imbalance and poor mobility:

  • Keep your bowels moving. People who move around less may become constipated (see managing side effects - constipation for additional information).
  • Take deep breaths. It is necessary to circulate air from the bottom of their lungs and out of your lungs (oxygenation), to prevent infection and pneumonia. This is especially important if you suffer from poor mobility. Using an incentive spirometer for 15 minutes a day, twice a day, can help promote oxygenation.
  • If you smoke, you should quit. If you do not smoke, avoid smoke-filled rooms. Smoking can affect the way your medications work. Discuss with your healthcare provider techniques that can help you quit.
  • Change position often (every 2 hours) to relieve pressure points.
  • Move legs and arms. Use "pressing down the gas petal" motion, or make circling motions with your ankles to help prevent blood clots.


  • Depending on the cause of imbalance and poor mobility problems, your symptoms of weakness may last a few days to a few months. It is important to follow all the instructions your healthcare provides.
  • Exercise, under the supervision of your healthcare provider such as walking, swimming, or light aerobic activity may help you to lose weight, and promote the flow of oxygen in your lungs and blood (oxygenation). Do not
  • Make sure to get enough sleep at night. This may help to lessen trouble in the daytime with incoordination, fatigue and weakness. If you have trouble sleeping:
  • Do not eat or exercise within 2 hours of bedtime
  • Make the room dark
  • If you have an electronic clock, or one with an illuminated face, turn the face away from you.
  • Use the bed only for sleeping
  • Keep a consistent schedule. Make sure you go to bed each night and wake up each morning, at the same time.
  • Minimize daytime naps. If you must take a nap, do not sleep for more than an hour at a time. Longer naps will make you feel more tired, worsen asthenia and interrupt nighttime sleep.
  • If these techniques do not work, consult your healthcare provider.
  • If you experience weakness symptoms or side effects, especially if severe, be sure to discuss them with your health care team. They can prescribe medications and/or offer other suggestions that are effective in managing such problems.

Drugs that may be prescribed by your doctor to treat weakness:

  • Treatment of your weakness is based upon finding the underlying cause, and treating that condition.
  • If your weakness is a result of a medication or treatment, removing that medication may help.
  • Depending on your overall health status, your doctor may recommend certain drugs that may help you. Some of the common drugs that are used to treat your weakness may include:
  • Antibiotics - If your doctor or healthcare provider suspects that you have an infection that has caused your ataxia, he or she may order antibiotics, either in a pill form or intravenous (IV). If you are prescribed antibiotics, take the full prescription. Do not stop taking pills once weakness is gone.
  • Antidepressants - are used to treat depression and pain in adults. People who have pain for a long period of time (chronic), or due to your situation, may become tired and depressed. This will lead to weakness.
  • Medications, such as venlafaxine (Effexor®) works by blocking the "reuptake" of the neurotransmitters serotonin and norepinephrine, thus decreasing your depressive symptoms along with weakness.
  • Corticosteroids: Corticosteroids work by decreasing inflammation (swelling) in many areas of the body.
  • You may be taking steroids if you have pain, or weakness due to tumors in your brain, or near your spinal cord.
  • Steroids will decrease the swelling in areas where tumors are located, which may decrease the pressure of the tumor on your nerve endings, and decrease your pain.
  • Erythropoeitin is a substance that your body produces naturally. This is a protein normally produced by the kidneys, which helps make red blood cells. Epoetin alfa and darbepoetin alfa are similar drugs that act like this natural substance to stimulate red blood cell production. During chemotherapy, patients may not be able to produce enough red blood cells, a condition known as anemia. Erythropoetic agents can treat anemia by increasing the number of red blood cells in the body.
  • Hemoglobin is the iron-containing substance in red blood cells that delivers oxygen throughout the body. Anemia and resulting decrease in circulating oxygen may contribute to confusion and cognitive problems. The normal hemoglobin range is approximately 12 to 18 g/dL, and varies according to age and gender. Doctors may prescribe erythropoetic agents to chemotherapy patients whose hemoglobin levels have fallen below normal levels.
  • Narcotics -The central nervous system (CNS) is a way for our brain to send messages to our body in a timely manner. It is highly alert, especially when we are experiencing pain. You may develop weakness or fatigue from chronic pain. Many narcotic analgesic (pain medicines) work by blocking pain messages, such as morphine sulfate and oxycodone.
  • Make sure you discuss with your healthcare provider common side effects, such as constipation, drowsiness, nausea and vomiting, and how to control these side effects.
  • Fatigue and weakness can be a side effect of pain medications, discuss with your healthcare provider how you may be able to control your symptoms of fatigue and weakness.
  • Non-steroidal anti-inflammatory (NSAID) agents or Tylenol®- NSAID's such as naproxen sodium and ibuprofen, may provide relief of many types of pain. Pain relief may help improve mobility, and alleviate weakness.
  • If you are to avoid NSAID drugs, because of your type of cancer or chemotherapy you are receiving, acetaminophen (Tylenol®) up to 4000 mg per day (two extra-strength tablets every 6 hours) may help.
  • It is important not to exceed the recommended daily dose of Tylenol®, as it may cause liver damage. Discuss this with your healthcare provider.

Other therapies:

  • Blood transfusion to treat severe anemia.
  • Physical therapy or Occupational therapy assistance may be prescribed.

When to Contact Your Doctor or Health Care Provider:

  • Changes in your walking, or imbalance problems.
  • You've fallen.
  • If your weakness progressively worsens.
  • If you have a headache, blurred vision, numbness or tingling.
  • If there is a change in mental status, such as confusion, disorientation, or increased sleepiness.
  • Difficulty with tasks such as writing your name, changing position from sitting to standing.
  • Extreme fatigue (unable to carry on self-care activities).
  • Fever of 100.5° F (38° C), and /or chills (possible signs of infection if you are receiving chemotherapy).

Note: We strongly encourage you to talk with your health care professional about your specific medical condition and treatments. The information contained in this website about weakness and other medical conditions is meant to be helpful and educational, but is not a substitute for medical advice.

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