What's Causing Your Numbness?

How do you know if that weird numbness you're experiencing is worrisome or not? Usually, numbness is temporary and not serious, but only your doctor can tell if it indicates trouble. We've got a rundown on common causes for numbness, which ones are serious and which are just a nuisance.

What causes numbness? That uncomfortable pins and needles or tingling sensation or complete loss of feeling is usually caused by irritation or compression of a nerve or group of nerves. For example, if you sit or sleep for too long in one position, you may reduce blood supply or compress nerves in one body part. 

Numbness can also result from minor nerve irritations like when you bang your elbow on the counter or major injuries like surgery. Lack of blood supply, caused by cardiac and circulatory diseases, can cause numbness as can chronic pressure from narrow nerve passages. Sometimes, numbness is the result of nerve compression from damaged or misaligned spinal discs and sometimes nerves become damaged from disease.

Where does numbness happen?  The most common places for numbness to occur are hands, feet, arms and legs, though it can occur anywhere on the body.   

When is numbness serious? Most causes of numbness are temporary and not serious, but sometimes they signal diseases that require medical attention. The National Institutes of Health lists these diseases and conditions that include numbness as a symptom:

  • Atherosclerosis
  • Frostbite
  • Carpal tunnel syndrome
  • Diabetes
  • Migraines
  • Multiple Sclerosis
  • Seizures
  • Strokes
  • Transient ischemic attack
  • Hypothyroidism
  • Raynaud's phenomenon
  • Abnormal calcium, potassium, or sodium levels
  • Vitamin B12 or other vitamin deficiency
  • Certain medications
  • Nerve damage due to lead, alcohol, or tobacco
  • Radiation therapy
  • Animal bites
  • Insect, tick, mite, and spider bites
  • Seafood toxins

When is numbness an emergency? Call 911 and seek emergency medical attention whenever numbness:

  • Comes on suddenly
  • Is a result of serious injury to the head, neck or back
  • Includes an entire body part
  • Is accompanied by weakness, paralysis, confusion, dizziness, severe headache, slurred speech, loss of bowel or bladder control or loss of consciousness

How will your doctor diagnose your numbness? 

Your doctor will ask questions about your health history and the location and nature of your numbness.  She'll want to know where it is, when it started, if it comes and goes, what makes it worse or better, if it's associated with any particular activities and if there are any other symptoms like pain or skin color changes associated with it. She'll do a physical exam and might order lab or diagnostic imaging tests to determine underlying causes for your numbness including:

Blood tests:

  • Complete blood count
  • Electrolyte levels
  • Vitamin levels
  • Heavy metal or toxicology screening


Imaging tests:

  • Angiogram(x-rays that use a special dye to visualize the inside of blood vessels)
  • CT scans
  • MRI
  • Ultrasound
  • X-rays

Other tests:

  • Nerve conduction studies and electromyography
  • Lumbar puncture (spinal tap) to look for central nervous system disorders
  • Cold stimulation tests

How Do you Treat Numbness?

Once your doctor has determined the cause of your numbness he'll determine a treatment plan to prevent or relieve numbness or reduce damage caused by numbness.  That might mean:

  • Changing your medications
  • Improving your diet
  • Physical therapy
  • Occupational therapy
  • Exercise
  • Surgery
  • Adopting new lifestyle techniques.

Your treatment plan may include a combination of medical and lifestyle interventions.  For example:

  • If your numbness is caused by diabetes, your doctor might prescribe diet and medication to lower your blood sugar plus exercise and occupational therapy to prevent further injury.
  • If it's caused by carpal tunnel syndrome, she might recommend surgery to release trapped nerves and protective devices and work accommodations to prevent recurrence.
  • If he diagnosis a medical condition like multiple sclerosis, treatment might include medication plus a diet, exercise and stress reduction plan.

Seek medical attention whenever you experience unusual numbness. Most of the time it's no cause for concern, but sometimes it's the vital clue that something serious is going on with your health. Let your doctor be the one to decide.


National Institutes of Health

Medline Plus

Numbness and Tingling