Weakness is reduced strength in one or more muscles.
Lack of strength; Muscle weakness
Weakness may be all over the body or in only one area, side of the body, limb, or muscle. Weakness is more noticeable when it is in one area. Weakness in one area may occur:
Weakness may be subjective or objective:
- Subjective means you feel weak, but there is no real loss of strength. For example, you may feel weak if you have an infection such as mononucleosis or the flu .
- Objective means there is a loss of strength that can be noted during a physical exam.
Weakness may be caused by a variety of conditions, including:
BRAIN/NERVOUS SYSTEM (NEUROLOGIC)
Follow the therapy your health care provider recommended to treat the cause of the weakness.
Call your health care provider if
Call your health care provider if you have:
- Sudden weakness, especially if it is in one area and does not occur with other symptoms, such as fever
- Sudden weakness after a viral illness
- Unexplained weakness that does not go away
- Weakness in one area of the body
What to expect at your health care provider's office
The health care provider will examine you and ask questions about your medical history and symptoms, such as:
- Time pattern
- Factors that make the weakness worse
- Relieving factors
- Other symptoms
- Other important information
The physical examination may include special attention to your heart, lungs, and thyroid gland. If there is a local area of weakness, the examination will focus on the nerves and muscle.
Tests that may be done include:
Griggs RC, Jozefowicz RF, Aminoff MJ. Approach to the patient with neurologic disease. In: Goldman L, Ausiello D, eds. . 24th ed. Philadelphia, Pa: Saunders Elsevier; 2011:chap 403.
Chinnery PF. Muscle diseases. In: Goldman L, Ausiello D, eds. . 24th ed. Philadelphia, Pa: Saunders Elsevier; 2011:chap 429.