Causes of Tingling and Numbness (Paresthesia)

What Means Tingling, Numbness and Paresthesia?

Paresthesia (Greek para- = abnormal, esthesia = feeling) is abnormal sensation on the skin that has no apparent physical cause (1). Affected persons may describe it as tingling, numbness, feeling of pins and needles, loss of sensation, tickling, pricking, creeping, skin crawling, burning, or itchiness. It may occur at any part of the body; it commonly appears on limbs, fingers, toes, face or entire head. Comparing affected and unaffected skin areas can help in determining, if paresthesia is present.

Symptoms of Paresthesia

Skin sensibility is enabled by nerves arising from the spinal cord, and some brain nerves arising from the brain-stem. The skin area innervated by a single nerve root is called a dermatome (Latin derma = skin, tome = section), (picture 1). Paresthesia occurs in skin parts that are innervated by affected nerve.

Picture 1. Dermatomes in Human

Paresthesia happens without warning, is usually painless, and may be felt like tingling, numbness, reduced or absent sensation, feeling of “pins and needles”, prickling, tickling, creeping, skin crawling, burning or itching. Sensitivity of the affected skin part may be increased, but it is usually decreased. Other symptoms like pain, muscular weakness, cramps, warmth or cool feeling, or change of skin color may appear – depending on the nature of the underlying disease.

How Paresthesia Occurs?

Sensations from the skin are carried via peripheral sensory nerves through the spinal cord (or via brain nerves and brain stem) into the brain. Disorder at any level of this neural pathway can cause paresthesia.

Causes of Transient Paresthesia

Transient paresthesia, often described as feeling of “pins and needles”, may be due to:

• Obdormition – numbness caused by prolonged pressure on the nerve, like when you cross your legs and leg falls asleep, or in lack of movement. Such paresthesia disappears gradually as the pressure is relieved.
• Whiplash
• Hyperventilation syndrome
• Panic attack
• Dehydration
• Transient Ischemic Attack (TIA), sometimes referred as “mini stroke”
• Beta-alanine ingestion
• Seizures
• Raynaud phenomena
• Insufficient blood supply in atherosclerotic arteries in legs (in Burger disease, paresthesia ia accompanied with calf pain)

Causes of Chronic Paresthesia

Prolonged, chronic paresthesia may be due to:

• Brain, spinal cord or peripheral nerve disorder: trauma, stroke, intra-cerebral hemorrhage, multiple sclerosis, tumors, encephalitis, meningitis, herniated disc, cervical spondylosis, pressure on the nerve (carpal tunnel syndrome), repetitive motion or prolonged vibration, neuralgia
• Heart and vessels disorders: angina pectoris, atherosclerosis, acute arterial occlusion, vasculitis, Raynaud disease, vertebrobasilar circulatory disorders
• Metabolic and hormonal disorders: diabetes, low blood sugar, hypothyroidism, hypoparathyroidism, hypoaldosteronism (Conn syndrome), menopause, abnormal blood levels of calcium, potassium, or sodium, uremia, porphyria
• Infections and post-infection syndromes: Lyme disease, HIV, leprosy, Guillain-Barré syndrome, Herpes zoster, Herpes simplex, rabies, Tabes dorsalis, canker sores, arbovirus
• Connective tissue and autoimmune diseases: rheumatoid arthritis, systemic lupus erythematosus (SLE), Sjögren’s syndrome, pernicious anemia 
• Blood disorders: thrombosis, polycythemia, thrombocytosis, leukemia
• Bones and joints disorders: arthritis, osteomalacia
• Fibromyalgia
• Nutrient deficiency: vit B1deficiency (beriberi), vit B5 and B12 deficiency
• Malignancies
• Skin disorders: burns, frostbite, Ito syndrome, acrodynia, acroparesthesia
• Migraine
• Psychological disorders: anxiety, panic attack, psychiatric disease
• Medications: anti-convulsant drugs, lomotil, SSRI withdrawal, amiodarone, colistimethate, digoxin, dimercaprol, mefloquine, riluzole , tetrodotoxin, thallium, topiramate, overdose of lidocain or vit B6
• Alcohol, tobacco, illegal drugs
• Poisoning: heavy metals (arzenic, lead, mercury), long term exposure to Nitrous oxide, ciguatera poisoning , snake bites , carbon monoxide
• Radiation exposure, or chemotherapy
• Hereditary diseases: Refsum syndrome, Fabry disease, Charcot-Marie-Tooth disease (a hereditary disorder that causes wasting of the leg muscles), porphyria, Denny-Brown’s syndrome (a hereditary disorder of the nerve root), ataxia-teleangiectasia
• Immune deficiency

Symptoms that often accompany paresthesia are pain, itching, feeling of cold or warmth, or burning. Reduced muscular power, abnormal reflexes or cramps may also be present in some diseases.

Diagnosis of the Cause of Paresthesia

1. Before appointment with the doctor, answer the following questions:

• On which parts of your body you feel tingling or numbness, and is it limited to one side of the body (left or right)? By which word you can describe the tingling: numbness, loss of sensation, pricking, creeping, burning, itching, pins and needles…?
• When has tingling started, is it permanent or transient? Does tingling change throughout the day?
• What triggers tingling: warmth, exercise, sitting for long periods of time, food, medications…?
• Other symptoms on affected body part: pain, skin color change, warmth, coolness, cramps, loss of muscular power?
• Any other general symptoms like fever or headache?
• Do you have any chronic disease like diabetes or rheumatoid arthritis? Were you injured or admitted to the hospital in the past from some reason? Which diagnoses you have or had so far?
• Does your work require repetitive motion, are you affected by constant vibrations, or exposed to certain chemicals like nitrogen oxide or carbon monoxide?
• Are you under stress, are you anxious?
• What’s your diet, do you drink alcohol, do you smoke, which medications or drugs are you taking?

2. Doctor will examine you, what includes detailed neurological examination.

3. Doctor may order the following tests:

• MRI or CT of the head and/or spine
• MRI, CT, or X-ray investigation of the chest, abdomen, bones or joints
• Blood tests: CBC, sedimentation rate, electrolytes, vitamins, sugar, sedimentation rate, proteins, thyroid hormones, heavy metals, drugs, antibodies to certain microbes, etc
• Urine tests: glucose, proteins, etc
• Electromyography (EMG) and nerve conduction tests
• Lumbar puncture (only when central nervous system disorders like multiple sclerosis or meningitis are suspected)
• Vascular ultrasound and a cold stimulation test to check for Raynaud’s phenomenon
• Nerve biopsy, if needed

Treatment of Paresthesia

Treatment of paresthesia depends on the cause. Paresthesia is usually treated by neurologist.

Home Care

Numbness after prolonged sitting or uncomfortable body position usually goes away after restoring circulation by stretching, or massaging the affected limb. If the underlying cause cannot be treated, aspirin or ibuprofen can be tried. In more difficult cases, low dose of antidepressant drugs such as amitriptyline are sometimes prescribed to alter body’s perception of pain. In severe cases, opiates, as codeine, can be prescribed (3).

In nutritional deficiency, supplements like B complex vitamins, especially vitamin B 12 can be tried (3).

Alcohol should be avoided. Self-massage with aromatic oils or ointments containing capsaicin may give temporary relief. Wearing lose shoes, gloves and clothes may also be helpful (3).

Call Emergency if:

• you feel weak, walk difficulty, hardly move an arm, have problems with speech or vision
• you can’t control your bladder or bowel
• you feel numbness after an injury
• you’ve lost consciousness, even if only for a while

Call your Doctor if:

• numbness has no obvious cause
• numbness is worse during walking
• you have pain, cramps, dizziness
• you are urinating more often
• you have a rash

Prognosis of Paresthesia

There is no known long-term physical effect from paresthesia (2). Prognosis depends on the underlying cause.

Further Reading About Tingling, Numbness and Itch

Numbness of Head, Face and Neck
Tingling and Numbness in Arm, Hand and Fingers
Numb Feet and Toes
Numbness in Both Hands and Feet
Itchy Skin – Causes
Itchy Face, Facial Rash
Types of Skin Rashes

References:

1. Paresthesia Definition
   http://www.medterms.com/script/main/art.asp?articlekey=4780
2. Causes of Paresthesia
   http://www.paresthesia.info/
3. Treatment of paresthesia
   http://neurology.health-cares.net/paresthesia-treatment.php
4. Disorders of a Single Peripheral Nerve and Numbness
   http://www.merck.com/mmhe/sec06/ch095/ch095f.html#sec06-ch095-ch095f-1467b
5. Causes of Paresthesia
   http://www.wrongdiagnosis.com/symptoms/numb_face/book-causes-5a.htm
   http://www.wrongdiagnosis.com/symptoms/numb_face/book-causes-8a.htm
6. Diagnosis of Paresthesia
   http://www.wrongdiagnosis.com/symptoms/numb_face/book-causes-10a.htm