Most commonly encountered by diabetics, peripheral neuropathy is a progressive loss of nerve function at the distal end of the nerves, most commonly in the foot.

Many current theories attribute this condition to an excessive elevation of sugar (glucose) in the blood over a period of many months to years. Over time, the excess sugar is converted to a byproduct, called sorbitol.

Over time, sorbitol collects inside the outer covering of the nerves. The accumulation of the sorbitol draws water into this nerve sheath, which overtime, places pressure on the nerve. It is the pressure of the water/sorbitol within the nerve sheath that places direct pressure on the nerve, causing the symptoms of burning, tingling, feeling like the feet are on fire, and eventually numbness.


Symptoms are very often equal in both feet, and are described as feeling as though the feet were asleep. Patients frequently have to sleep with their feet out from under the covers due to the sensation of the feet being very hot. In severe cases, patients even try to attain relief by soaking their feet in ice water, which doesn't seem to help the condition a great deal.

By far, the most common cause of neuropathy is diabetes, although it is possible to have the condition without being diabetic. For diabetics, the main way to prevent or slow the development of neuropathy is though maintaining a normal sugar level (80-120mg/dL). Large fluctuations in sugar level throughout the day can contribute to the development of neuropathy.

Diagnosing neuropathy, in my opinion, is clinical. Some may find benefit in a nerve conduction velocity (NCV) study which measures the speed of transmission of various nerves in the body. I do not believe this is beneficial, as neuropathy is a disease at the nerve endings. The nerve endings at the level of the skin are those which become damaged, and not the large nerves in the thigh or leg. A nerve conduction velocity study is a test on the large nerves of the leg. Likewise, an MRI is of no benefit, as the problem will not display any abnormality on an MRI.

Treatment is available which is geared towards reduction of symptoms. Eventually, the numbness and tingling sensations will be replaced by numbness. Until that point, medications can be taken to reduce these symptoms.

By far, the most common type of neuropathy is sensory, where the patients experience this burning, tingling sensations. Motor neuropathy is also possible, where the damage to the nerves causes atrophy of the small muscles of the foot. This condition often results in development of hammer (contracted) toes, bunions, and other foot deformities.

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