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What is weakness?

Weakness is a loss of muscle strength or energy. You may have weakness in a single muscle or in a group of muscles.

What causes weakness?

The exact cause of your weakness may not be known. Weakness may also have more than one cause. Your weakness may be caused by the following:

  • Nerve or muscle problems: Weakness may be caused by a problem in your brain, nerves, or muscles.
  • Physical and mental conditions: Physical conditions such as dehydration, heart problems, infection, or pregnancy may also cause weakness. Mental problems, such as anxiety or depression, are also possible causes.
  • Drug reactions: Weakness may be a side effect of drugs such as steroids, heart medicine, or muscle relaxants. Alcohol or illegal drugs can also cause weakness.
  • Prolonged lack of motion: Parts of your body may become weak if you have not moved them for a long time. This may happen if you wear a cast or splint or if you are on bed rest.

What are the signs and symptoms of weakness?

  • You have trouble with daily tasks such as grooming, writing, using keys or zippers, or opening doors.
  • You have trouble standing, lose your balance often, or stumble when you walk. You have trouble lifting yourself out of the bathtub or using stairs. You sprain your ankle often.
  • You have trouble whistling, drinking from a straw, or blowing up a balloon.
  • You have speech problems or trouble swallowing. You drool or have changes in your facial expressions.
  • You have double or blurred vision, or your eyelids droop.
  • You have trouble breathing or holding your head up.
  • You cannot stand up straight.

How may the cause of my weakness be diagnosed?

Your caregiver will ask when your signs and symptoms started and what makes your weakness worse. He may ask what medicines you take and if you have recently had a cast or been on bed rest. He will ask what medical conditions you have or if any family members have had muscle weakness. He will test your muscle strength, reflexes, and sense of touch. He will also check how far you can move or lift your weakened area. Tell him all other signs and symptoms you have, such as pain, tiredness, and numbness. Also tell him if you have trouble breathing, swallowing, or urinating, or fever and cold symptoms. You may also receive the following:

  • Blood tests: A sample of your blood may be sent to a lab for tests to help find the cause of your weakness. The blood may be taken from your hand, arm, or IV.
  • Muscle biopsy: Your caregiver may remove a small piece of your weakened muscle and send it to a lab for tests. This may happen if your blood tests do not show the cause of your weakness. Ask your caregiver for more information if you need a muscle biopsy.
  • Imaging tests: You may need imaging tests such as x-rays. These tests take pictures of the inside of your body. The pictures may show your caregiver what is causing your weakness.

How is weakness treated?

You may be admitted to the hospital if your signs and symptoms are severe. You may also be admitted based on the types of symptoms you have. You may also need the following:

  • Assistive devices: Protect yourself from injury. Have someone install handrails in your home. These will help you get out of a bathtub or stand up from a toilet. Get help going up and down stairs if your legs are weak.
  • Range-of-motion exercises and splints: Your caregiver will teach you exercises to help increase movement in your weakened body part. This will happen if you have chronic (long-term) weakness. Your caregiver may also place a splint on your affected body part if you have chronic weakness. Ask your caregiver for more information about exercises and splints.
  • Pain medicine: You may be given medicine to decrease pain. Do not wait until the pain is severe before you take your medicine.

How can I manage my weakness?

  • Rest: Avoid exercise that makes your weakness worse, and get plenty of rest. Ask your caregiver how much exercise is right for you. Rest your mind as well as your body. Try to avoid stress if possible. Stress may make your symptoms worse.
  • Eat the right amount of food: Too much or too little food may cause weakness or tiredness. Ask your caregiver what a healthy amount of food is for you.
  • Avoid caffeine, alcohol, cigarette smoking, and illegal drugs: These things may cause muscle twitching, which could lead to worsened weakness.

When should I contact my caregiver?

Contact your caregiver if:

  • You feel depressed or anxious.
  • You have questions or concerns about your symptoms.

When should I seek immediate care?

Seek care immediately or call 911 if:

  • You have any of the following signs of a heart attack:
    • Squeezing, pressure, or pain in your chest that lasts longer than 5 minutes or returns
    • Discomfort or pain in your back, neck, jaw, stomach, or arm
    • Trouble breathing
    • Nausea or vomiting
    • Lightheadedness or a sudden cold sweat, especially with chest pain or trouble breathing
  • You have any of the following signs of a stroke:
    • Numbness or drooping on one side of your face
    • Weakness in an arm or leg
    • Confusion or difficulty speaking
    • Dizziness, a severe headache, or vision loss
  • You lose feeling in your weakened body area.
  • You have electric shock-like feelings down your arms and legs when you flex or move your neck.
  • You have severe pain in your back, arms, or legs that worsens.
  • You have sudden or increased trouble speaking, swallowing, or breathing.
  • You have sudden or worsened muscle weakness or loss of movement.
  • You are not able to control when you urinate or have a bowel movement.

Care Agreement

You have the right to help plan your care. Learn about your health condition and how it may be treated. Discuss treatment options with your caregivers to decide what care you want to receive. You always have the right to refuse treatment. The above information is an educational aid only. It is not intended as medical advice for individual conditions or treatments. Talk to your doctor, nurse or pharmacist before following any medical regimen to see if it is safe and effective for you.

© 2015 Truven Health Analytics Inc. Information is for End User's use only and may not be sold, redistributed or otherwise used for commercial purposes. All illustrations and images included in CareNotes® are the copyrighted property of A.D.A.M., Inc. or Truven Health Analytics.