numbness causes

Overview

Numbness describes a loss of sensation or feeling in a part of your body. It's often accompanied by or combined with other changes in sensation, such as a pins-and-needles feeling or burning. Numbness can occur along a single nerve on one side of the body, or it may occur symmetrically, on both sides of the body. 

Causes

Numbness is often caused by damage, irritation or compression of nerves. A single nerve branch or several nerves may be affected, as with a slipped disk in the back or carpal tunnel syndrome in the wrist. Certain diseases — such as diabetes, which can damage the longest, most sensitive nerve fibers (such as those going to your feet) — also can cause numbness.

Numbness commonly affects nerves located on the periphery of your body. Numbness alone isn't usually associated with potentially life-threatening disorders, such as strokes or tumors.

Your doctor will need detailed information about your symptoms to diagnose the cause of your numbness. A variety of tests may be needed to confirm the cause before appropriate treatment can begin.

Possible causes of numbness in one or both of your hands include:

Brain and nervous system conditions

  1. Acoustic neuroma
  2. Brain aneurysm
  3. Brain AVM (arteriovenous malformation)
  4. Brain tumor
  5. Guillain-Barre syndrome
  6. Herniated disk
  7. Paraneoplastic syndromes of the nervous system
  8. Peripheral nerve injuries
  9. Peripheral neuropathy
  10. Spinal cord injury
  11. Spinal cord tumor
  12. Stroke
  13. Transient ischemic attack (TIA)
  14. Transverse myelitis

Trauma or overuse injuries

  1. Brachial plexus injury
  2. Carpal tunnel syndrome
  3. Frostbite

Chronic conditions

  1. Alcohol use disorder
  2. Amyloidosis (buildup of abnormal proteins in your organs)
  3. Charcot-Marie-Tooth disease
  4. Diabetes
  5. Fabry's disease
  6. Multiple sclerosis
  7. Porphyria
  8. Raynaud's disease
  9. Sjogren's syndrome

Infectious diseases

  1. Leprosy
  2. Lyme disease
  3. Shingles
  4. Syphilis

Treatment side effects

  1. Side effects of chemotherapy or anti-HIV drugs

Other causes

  1. Heavy metal exposure
  2. Thoracic aortic aneurysm
  3. Vasculitis
  4. Vitamin B-12 deficiency

When to see a doctor

Numbness can have a variety of causes. Most are harmless, but some can be life-threatening.

Call 911 or seek emergency help if your numbness:

  • Begins suddenly
  • Follows a recent head injury
  • Involves an entire arm or leg

Also seek emergency medical care if your numbness is accompanied by:

  • Weakness or paralysis
  • Confusion
  • Difficulty talking
  • Dizziness
  • Sudden, severe headache

You are likely to have a CT scan or MRI if:

  • You've had a head injury
  • Your doctor suspects or needs to rule out a brain tumor or stroke

Schedule an office visit if your numbness:

  • Begins or worsens gradually
  • Affects both sides of the body
  • Comes and goes
  • Seems related to certain tasks or activities, particularly repetitive motions
  • Affects only a part of a limb, such as your toes or fingers

Differential diagnoses

Acute flaccid myelitis (AFM)

Arteriosclerosis / atherosclerosis

Arteriovenous malformation

Brachial plexus injury

Brachial plexus surgery

Brain aneurysm

Carotid artery disease

Cavernous malformations

Cervical spondylosis

Charcot-Marie-Tooth disease

Chronic exertional compartment syndrome

Diabetic neuropathy

Dislocated shoulder

Dislocation

Eisenmenger syndrome

Essential thrombocythemia

Fibromuscular dysplasia

Frostbite

Functional neurologic disorders/conversion disorder

Golfer's elbow

Heart disease

Herniated disk

Jellyfish stings

Lead poisoning

Lyme disease 

Meralgia paresthetica

Metatarsalgia

Migraine with aura

Monoclonal gammopathy of undetermined significance (MGUS)

Morton's neuroma

Multiple myeloma

Multiple sclerosis

Neurofibromatosis

Paget's disease of bone

Paraneoplastic syndromes of the nervous system

Peripheral artery disease (PAD)

Peripheral nerve tumors

Peripheral neuropathy

Pinched nerve

Polycythemia vera

Porphyria

Postherpetic neuralgia

Raynaud's disease

Salivary gland tumors

Sciatica

Shingles

Spinal cord injury

Spinal stenosis

Syringomyelia

Thrombocytosis

Transient ischemic attack (TIA)

Transverse myelitis

Traumatic brain injury

Vasculitis

Vitamin deficiency anemia