Numbness
Numbness is loss or reduction of normal sensation, often described as feeling 'asleep' or 'dead'. It can affect a small area or a whole limb, and may signal anything from a temporary pinched nerve to a serious neurologic problem.
Table of Contents
Quick Facts
- ICD-10: R20.0
- Common locations: Hands, feet, face
- Emergency?: Sometimes — see warning signs
When to Call 911
- Face — drooping on one side
- Arm — weakness or numbness in one arm
- Speech — slurred or strange speech
- Time — call 911 immediately
Also call 911 for sudden numbness with: severe headache, vision changes, confusion, difficulty walking, or chest pain.
Understanding Numbness
Sensation depends on intact nerves carrying signals from the skin to the brain. Pressure, damage, or disease anywhere along this pathway can produce numbness, tingling, or both. Whether numbness is harmless or serious depends on the cause, distribution, and how quickly it came on.
Common Causes
Pressure or position-related
- Sitting or sleeping in one position too long
- Carpal tunnel syndrome
- Cubital tunnel syndrome (ulnar nerve)
- Cervical or lumbar disc problems
Nerve disorders
- Peripheral neuropathy from diabetes, alcohol, chemotherapy, or vitamin deficiency
- Shingles
- Multiple sclerosis
- Guillain-Barré syndrome
Vascular
- Stroke or transient ischemic attack (TIA)
- Reduced blood flow to a limb
Other
- Migraine aura
- Anxiety and hyperventilation (often around the lips and fingers)
- Low blood sugar
- Vitamin B12 deficiency
Diagnosis
Evaluation depends on the pattern and other symptoms. Tools may include:
- Neurologic exam
- Blood tests (glucose, B12, thyroid, kidney function)
- Nerve conduction studies / EMG
- Imaging (MRI of brain or spine)
Treatment
Treatment depends on the cause:
- Position changes and wrist splints for carpal tunnel
- Tight diabetes control for diabetic neuropathy
- B12 replacement when deficient
- Treatment of stroke or autoimmune disease
- Physical therapy and occupational therapy
When to See a Doctor
See a doctor for numbness that:
- Is persistent or progressive
- Affects both feet or both hands
- Is associated with weakness or difficulty walking
- Develops after an injury
- Comes with bowel or bladder changes
Frequently Asked Questions
Sleeping with your arm under your head or in a cramped position can compress nerves and reduce blood flow, causing temporary numbness that resolves with movement. Frequent nighttime numbness, especially in the same hand, may indicate carpal tunnel syndrome.
MS can cause numbness, but most numbness is not from MS. Patterns suggesting MS include episodes that come and go, often with other neurologic features.
Raynaud's phenomenon — small blood vessels constrict in response to cold — can cause finger or toe numbness, color changes, and pain. Usually benign, but can be associated with autoimmune diseases.
References
- National Institute of Neurological Disorders and Stroke. Numbness and Tingling Information.