Weakness is reduced strength in one or more muscles.

Alternative Names

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:


Weakness may be caused by a variety of conditions, including:






Home Care

Follow the therapy your health care provider recommended to treat the cause of the weakness.

When to Contact a Medical Professional

Call your health care provider if you have:

What to Expect at Your Office Visit

The health care provider will examine you and ask questions about your medical history and symptoms, such as:

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. Cecil Medicine. 24th ed. Philadelphia, Pa: Saunders Elsevier; 2011:chap 403.

Chinnery PF. Muscle diseases. In: Goldman L, Ausiello D, eds. Cecil Medicine. 24th ed. Philadelphia, Pa: Saunders Elsevier; 2011:chap 429.

Review Date: 8/14/2012
Reviewed By: Linda J. Vorvick, MD, Medical Director and Director of Didactic Curriculum, MEDEX Northwest Division of Physician Assistant Studies, Department of Family Medicine, UW Medicine, School of Medicine, University of Washington. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M. Health Solutions, Ebix, Inc.
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