People have experienced paresthesia when they feel that their skin was crawling or had numbness or itching. Almost every single person experiences paresthesia on occasion. It is known that one of the most common times people get familiar feelings of needles and pins is when their legs or arms “fall asleep”. This sensation is usually happening because you have inadvertently put a pressure on nerve. This sensation resolves once you have changed your position to remove the pressure from the affected nerve. This is a temporary paresthesia and usually it goes on its own without treatment. But if you have noticed that paresthesia persists, then you may have underlying medical condition which requires treatment for paresthesia. 
This condition can affect any part of your body, but most commonly paresthesia is affecting:
The paresthesia can be temporary or chronic. The symptoms can include feelings of:
If you have a chronic paresthesia, then it can cause a stabbing pain. This type of pain can lead to clumsiness of the affected limb. When the paresthesia happens in your legs and feet, then this can be difficult to walk. If you have symptoms of paresthesia which persist of if they affect the quality of your life, then you should talk with your doctor as soon as possible.
It is not always possible to determine the real cause for paresthesia. Brief periods of poor circulation or pressure on the nerve can be a cause for the temporary paresthesia. This can happen when you sit with your legs crossed for too long or when you fall asleep on your hand. The chronic paresthesia can be a sign of nerve damage . There are 2 types of nerve damage which are causing chronic paresthesia – radiculopathy and neuropathy.
- Radiculopathy: This is a condition in which nerve roots become inflamed, irritated or compressed. This can happen when you have:
- Any mass that compresses the nerve as it exits the spinal column
- A narrowing of the canal that transmits the nerve from your spinal cord to your extremity
- A herniated disk that presses on a nerve
When the radiculopathy is affecting the lower back, then it is called radiculopathy. The lumbar radiculopathy can cause paresthesia in your foot or leg. When there are more severe cases, then the compression of the sciatic nerve can happen and it can lead to weakness in the legs. We know that the sciatic nerve is a large nerve which starts in the lower spinal cord. The cervical radiculopathy is involving the nerves which are providing sensation and strength to the arms. If you suffer from cervical radiculopathy, then you can experience:
- Hand weakness
- Arm weakness
- Paresthesia of the upper extremities
- Chronic neck pain
- Neuropathy: This condition is caused by chronic nerve damage . The high blood sugar or hyperglycemia is the most common cause for neuropathy. Here are other possible causes for neuropathy:
- Exposure to toxic substances, such as chemicals or heavy metals
- Certain medications, such as chemotherapy drugs
- Infections, such as Lyme disease, shingles or HIV
- Getting too much Vitamin D
- Deficiencies in vitamin B – 1, B – 6, B – 12, E or niacin
- Bone marrow or connective tissue disorders
- Tumors in the brain or near nerves
- Liver diseases
- Kidney diseases
- Neurological diseases, such as MS
- Autoimmune diseases, such as rheumatoid arthritis
- Repetitive movement injuries
The nerve damage can eventually lead to paralysis or permanent numbness.
Risk factors: Every single person can experience temporary paresthesia. As we are getting older, then we have increased chances of getting radiculopathy. Also you are having more chances of getting this condition if you:
- Have a neurological condition, such as MS 
- Have an autoimmune condition 
- Have type 1 or 2 diabetes 
- Drink heavily and eat a poor diet which leads to vitamin deficiencies, specifically folate and Vitamin B – 12 
- Do some repetitive movements that repeatedly compress your nerves, such as playing an instrument, typing or playing a sport such as tennis
 The Marshall Protocol Knowledge Base. Numbness (paresthesia and neuropathy). Retrieved from mpkb.org/home/symptoms/neurological/paresthesia
 National Institute of Neurological Disorders and Stroke. Peripheral neuropathy fact sheet. Retrieved from www.ninds.nih.gov/Disorders/Patient-Caregiver-Education/Fact-Sheets/Peripheral-Neuropathy-Fact-Sheet
 Kraker J, Živković SA. Autoimmune neuromuscular disorders.
Current Neuropharmacology. 2011;9(3):400–8.
 Bansal V, Kalita J, Misra UK. Diabetic neuropathy. Postgraduate Medical Journal. 2006;82(964):95–100.
 Staff NP, Windebank AJ. Peripheral neuropathy due to vitamin deficiency, toxins, and medications. Continuum (Minneap Minn). 2014;20(5 Peripheral Nervous System Disorders):1293–306.