Numbness

Numbness describes a loss of feeling in a part of the body. It also is often used to describe other changes in sensation, such as burning or a pins-and-needles feeling. Numbness can occur along a single nerve on one side of the body. Or numbness may occur on both sides of the body. Weakness, which is usually caused by other conditions, is often mistaken for numbness.

Numbness is caused by damage, irritation or compression of nerves. A single nerve branch or several nerves may be affected. Examples include a slipped disk in the back or carpal tunnel syndrome in the wrist. Certain diseases such as diabetes or toxins such as chemotherapy or alcohol can damage the longer, more-sensitive nerve fibers. These include the nerve fibers that go to the feet. The damage can cause numbness. Numbness commonly affects nerves outside of the brain and spinal cord. When these nerves are affected, it can cause a lack of feeling in the arms, legs, hands and feet. Numbness alone, or numbness associated with pain or other unpleasant sensations, isn't usually due to life-threatening disorders such as strokes or tumors. Your doctor needs detailed information about your symptoms to diagnose the cause of your numbness. A variety of tests may be needed to confirm the cause before treatment can begin. Possible causes of numbness include: Brain and nervous system conditions Acoustic neuroma Brain aneurysm Brain AVM (arteriovenous malformation) Brain tumor Guillain-Barre syndrome Herniated disk Paraneoplastic syndromes of the nervous system Peripheral nerve injuries Peripheral neuropathy Spinal cord injury Spinal cord tumor Stroke Transient ischemic attack (TIA) Transverse myelitis Trauma or overuse injuries Brachial plexus injury Carpal tunnel syndrome Frostbite Chronic conditions Alcohol use disorder Amyloidosis Charcot-Marie-Tooth disease Diabetes Fabry's disease Multiple sclerosis Porphyria Raynaud's disease Sjogren's syndrome (a condition that can cause dry eyes and a dry mouth) Infectious diseases Leprosy Lyme disease Shingles Syphilis Treatment side effects Side effects of chemotherapy or anti-HIV drugs Other causes Heavy metal exposure Thoracic aortic aneurysm Vasculitis Vitamin B-12 deficiency