Peripheral nerves are the ones that carry sensation from the   environment to the brain. They are part of a very efficient circuit where even a wisp of hair can be perceived by the individual in less than a fraction of a second.  Unfortunately these nerves can be damaged by various reasons resulting in altered or impaired sensations or loss of sensation. Altered sensations can be in the form of tingling, sensation of ants crawling, burning pain, cramps, e.t.c. If the sensations are impaired, while walking one feels as if walking on wool. There may be sensation of numbness or heaviness in the hands or feet. In extreme cases, there is loss of all sensations making one vulnerable to injury. The site of problems depends on the nerve or nerves affected. A single nerve may be affected causing sense of numbness in one limb or part of limb. This would have been experienced by everybody some time or other. If one sleeps keeping a hand below the head, he or she can wake up with that hand feeling numb. This sensation is temporary and resolves itself. A, "glove and stocking”, peripheral neuropathy is the one where both hands and feet are affected.    Peripheral neuropathy can be due to many reasons. Diabetic patients are very vulnerable to develop peripheral neuropathy as   high blood glucose damages the peripheral nerve fibers. It is one of the main reasons for development of diabetic foot. Here, due to peripheral neuropathy, a diabetic patient has impaired sensation on the feet. This results in repeated trauma and infections   that can result in deformities of the feet in severe cases. Chronic vitamin B. complex deficiency, particularly B1 (thiamine), B6 (pyridoxine) and B12 (cobalamin) results in peripheral neuropathy, as vitamin B. complex is very important for the functioning of nerves in the body. Peripheral neuropathy is one of the manifestations of chronic liver and kidney diseases.The nerves can also be affected by infectious diseases like herpes zoster, HIV and leprosy.Alcohol is also toxic to the peripheral nerves and people consuming alcohol can develop features of damage to peripheral nerves which increases in severity as consumption continues. Some drugs also cause peripheral neuropathy. Among them, fluroquinolones like ciprofloxacin, anti-tubercular drug like isoniazid, metronidazole used for intestinal protozoal infections, e.t.c. are some of the drugs which can cause peripheral neuropathy as adverse effect. Withdrawal of the offending drug helps in improvement of the symptoms. Radiation therapy and chemotherapy used to treat any malignancy can damage the peripheral nerves along with malignant cells resulting in abnormal or impaired sensations.One may have a peripheral neuropathy, due to one or more than one of the causes. But it is a troublesome condition, when one has abnormal or reduced sensations anywhere in the body. Often the sleep is also disturbed due to burning sensation in the hands and or feet. Due to severe parasthesias, a person finds it difficult   to work or even walk at timesTaking a nutritious diet rich in vitamin B. complex helps to prevent neuropathy due to vitamin B. complex deficiency. It also helps to minimize the suffering   due to peripheral nerve damage   resulting from other causes. Such a diet should include whole grain, cereals, nuts, red meat, e.t.c.Those who suffer from diabetes need to keep blood glucose levels well controlled by means of diet and drugs, to avoid peripheral neuropathy.  In early stages, neuropathy is reversible in diabetic patients.If one avoids or gives p alcohol, he can prevent many health hazards including that of peripheral neuropathy. Treatment consists of supplements of vitamin B. complex. Certain anti-epileptic drugs like gabba pentin and carbamazepine provide symptomatic relief in troublesome neuropathy. Antidepressant drugs are also used for the same purpose.Whenever a person develops altered sensations in the limbs or any part of the body, he should seek medical treatment before the problem is aggravated.Dr. Rachna Pande is a specialist-Internal medicine-Ruhengeri Hospital