Numbness and tingling

Sensory loss; Paresthesias; Tingling and numbness; Loss of sensation

There are many possible causes of numbness and tingling, including:

• Sitting or standing in the same position for a long time
• Injuring a nerve (a neck injury may cause you to feel numbness anywhere along your arm or hand, while a low back injury can cause numbness or tingling down the back of your leg)
• Pressure on the nerves of the spine, such as from a herniated disk
• Pressure on peripheral nerves from enlarged blood vessels, tumors, scar tissue, or infection
• Shingles or herpes zoster infection
• Lack of blood supply to an area, such as from atherosclerosis, frostbite, or vessel inflammation
• Abnormal levels of calcium, potassium, or sodium in your body
• A lack of vitamin B12 or other vitamin
• Use of certain medicines
• Nerve damage due to lead, alcohol, or tobacco, or from chemotherapy drugs
• Radiation therapy
• Animal bites
• Insect, tick, mite, and spider bites
• Seafood toxins

Numbness and tingling can be caused by other medical conditions, including:

• Carpal tunnel syndrome (pressure on a nerve at the wrist)
• Diabetes
• Migraines
• Multiple sclerosis
• Seizures
• Stroke
• Transient ischemic attack (TIA), sometimes called a "mini-stroke"
• Underactive thyroid
• Raynaud phenomenon (narrowing of the blood vessels, usually in the hands and feet)

Your health care provider should find and treat the cause of your numbness or tingling. Treating the condition may make the symptoms go away or stop them from getting worse. For example, if you have carpal tunnel syndrome or low back pain, your doctor may recommend certain exercises.

If you have diabetes, your doctor will discuss ways to control your blood sugar levels.

Low levels of vitamins will be treated with vitamin supplements.

Medicines that cause numbness or tingling may need to be switched or changed. DO NOT change or stop taking any of your medicines or take large doses of any vitamins or supplements until you have talked with your provider.

Because numbness can cause a decrease in feeling, you may be more likely to accidentally injure a numb hand or foot. Take care to protect the area from cuts, bumps, bruises, burns, or other injuries.

Go to a hospital or call your local emergency number (such as 911) if:

• You have weakness or are unable to move, along with numbness or tingling
• Numbness or tingling occur just after a head, neck, or back injury
• You cannot control the movement of an arm or a leg, or you have lost bladder or bowel control
• You are confused or have lost consciousness, even briefly
• You have slurred speech, a change in vision, difficulty walking, or weakness

Call your provider if:

• Numbness or tingling has no obvious cause (like a hand or foot "falling asleep")
• You have pain in your neck, forearm, or fingers
• You are urinating more often
• Numbness or tingling is in your legs and gets worse when you walk
• You have a rash
• You have dizziness, muscle spasm, or other unusual symptoms

Your provider will take a medical history and perform a physical examination, carefully checking your nervous system.

Medical history questions may include:

• What part or parts of your body have numbness or tingling? Your trunk? Your legs or feet? Your arms, hands, or fingers?
• Which side of your body is involved?
• Which area of that body part? For example, is your inner thigh, calf, or foot affected? Your palm, fingers, thumb, wrist, or forearm?
• Does the numbness or tingling affect your face? Around your eyes? Your cheeks? Around your mouth? Is one or both sides of your face involved?
• Does the part of your body with numbness or tingling change colors? Does it feel cold or warm?
• Do you have other abnormal sensations?
• Are you unaware of your body on the affected side?
• How long have you had the numbness or tingling?
• When did it start?
• Does anything make it worse, such as exercise or standing for long periods of time?
• Do you have any other symptoms?

Your provider may also ask you questions to determine your risk for stroke, thyroid disease, or diabetes, as well as questions about your work habits and medicines.

Blood tests may include:

• Complete blood count (CBC)
• Electrolyte level (measurement of body chemicals and minerals) and liver function tests
• Thyroid function tests
• Measurement of vitamin levels
• Heavy metal or toxicology screening
• Sedimentation rate and measurements of C-reactive protein

Imaging tests may include:

• Angiogram (a test that uses x-rays and a special dye to see inside the blood vessels)
• CT angiogram
• CT scan of the head
• CT scan of the spine
• MRI of the head
• MRI of the spine
• Ultrasound of neck vessels to determine your risk for TIA or stroke
• Vascular ultrasound
• X-ray of the affected area

Other tests that may be done include:

• Electromyography and nerve conduction studies to measure how your muscles respond to nerve stimulation
• Lumbar puncture (spinal tap) to rule out central nervous system disorders
• Cold stimulation test may be done to check for Raynaud phenomenon