Paresthesia refers to a burning or prickling sensation that is usually felt in the hands, arms, legs, or feet, but can also occur in other parts of the body. The sensation, which happens without warning, is usually painless and described as tingling or numbness, skin crawling, or itching.
Most people have experienced temporary paresthesia -- a feeling of "pins and needles" -- at some time in their lives when they have sat with legs crossed for too long, or fallen asleep with an arm crooked under their head. It happens when sustained pressure is placed on a nerve. The feeling quickly goes away once the pressure is relieved.
Chronic paresthesia is often a symptom of an underlying neurological disease or traumatic nerve damage. Paresthesia can be caused by disorders affecting the central nervous system, such as:
Nerve entrapment syndromes, such as carpal tunnel syndrome, can damage peripheral nerves and cause paresthesia accompanied by pain.
Diagnostic evaluation is based on determining the underlying condition causing the paresthetic sensations. An individual's medical history, physical examination, and laboratory tests are essential for the diagnosis. Physicians may order additional tests depending on the suspected cause of the paresthesia.
The prognosis for those with paresthesia depends on the severity of the sensations and the associated disorders.
The appropriate treatment for paresthesia depends on accurate diagnosis of the underlying cause. In addition to treating the underlying disorder, palliative care can include the use of topical numbing creams, such as Lidocaine or Prilocaine. Care must be take to apply only the necessary amount, as excess can contribute to the condition. Otherwise, these products offer extremely effective, but short-lasting, relief from the condition. Medications offered can include the immunosuppressant prednisone, intravenous gamma globulin (IVIG), anticonvulsants, and antiviral medication, amongst others.