Neuropathy is caused by damage or irritation to a nerve or group of nerves, which results in altered function or sensation. This can result in reduced or altered ability to sense or move the body in an area specific to the nerve affected. There are a number of things that can cause neuropathy, and there are also a wide variety of symptoms that can occur depending on the particular nerve or nerve type affected.

The types of neuropathy are generally classified by the type and number of nerves affected, and also by the underlying cause if it is known.

Signs and Symptoms
There are some signs and symptoms that are common to most types of neuropathy and these include changes in sensation or movement. Tingling, pain, itching, and loss of sensation are all possible symptoms, and each may occur at different times. Changes in movement can include weakness, heaviness, fatigue, gait abnormalities and cramping or twitching, as well as loss of function. The specific symptoms depend on the location and type of nerve affected.

Causes of Neuropathy
Systemic cases of neuropathy (those affecting multiple nerves throughout the body) are more commonly caused by autoimmune attack (like in Multiple Sclerosis), viral infection, systemic bacterial infection, toxic buildup, drug reactions, and/or underlying vitamin deficiency. Common infections are: herpes simplex (see Cold Sores article), Shingles, and Lyme Disease. The most common cause of chemical injury is the from the excess sugar of uncontrolled diabetes. See the paragraph on diabetic neuropathy below for more information. Other systemic causes are: Autoimmune Diseases, and vitamin deficiencies such as Vitamin B12, and Vitamin B1. Toxic reactions can be caused by heavy metals, or excess Vitamin B6. Common drugs that can cause neuropathy are: antifungals, nitrofurantoin, statins, and certain antibiotics. Be sure to let your healthcare practitioner know if you are taking any of these medications. Local problems are more likely caused by local infection, trauma, improper posture and poor body positioning. In many cases the underlying cause of neuropathy is unknown and conventional treatment will often focus on managing the symptoms.

Conventional Treatment
If the underlying cause is known, then all treatment methods will target this cause first. In all cases the symptoms will be managed with drugs for pain and discomfort. Common medications for management of neuropathy are tricyclic antidepressants, and antiepileptic medications like gabapentin. Interestingly, a large amount of research has been performed on the efficacy of cannabis for the treatment of neuropathy. In a number of cases medicinal marijuana has been found to significantly improve the symptoms, particularly in those with pain.

TYPES OF NEUROPATHY

Neuritis
The inflammation of a nerve is a condition known as neuritis. It can be caused by physical injury, infection, chemical injury, radiation, and even underlying vitamin deficiency. The symptoms of this condition can include any of the symptoms listed under peripheral and autonomic neuropathy below.

Mononeuropathy
When only a single nerve is affected by the symptoms, it is a condition known as mononeuropathy. Most commonly, this type of neuropathy is caused by irritation or damage of one nerve or nerve chain. Temporary cases of this occur all the time, and most of us have accidentally cut off the circulation to a limb (and its nerve) at some point and had a few minutes of “pins and needles” as a result. When certain muscles become too tense or developed, they can actually press the nerve against solid structures like bones and cause a similar effect. The most common chronic form of this type of neuropathy is Carpal Tunnel Syndrome. Common effects of this type of neuropathy are loss of sensation, paralysis, weakness and tingling, burning, and pain restricted to the area serviced by the affected nerve. Interestingly, this type of neuropathy is most commonly caused by physical constrictions caused by muscular imbalances, poor posture, and joint deterioration. In some cases it can also be cause by local trauma or infection. Changing the ergonomics of your every day actions and repeated motions can significantly improve symptoms and prevent surgical intervention. You can ask your healthcare practitioner for more information.

Diabetic Neuropathy
When blood sugar levels are not well regulated, there are periods of time when the blood contains excessive amounts of glucose. Over time, this causes sugar to build up on proteins in the blood, on the linings of the blood vessels, and even on the nerves themselves. This causes damage to the affected tissues, which leads to poor circulation in the extremities and altered pain sensations such as pain and numbness in the hands and feet. Over time this can lead to an increased risk of injury and the formation of diabetic ulcers. To prevent diabetic neuropathy, it is essential to maintain healthy balanced blood sugar levels at all times and avoid large fluctuations. For more information, please see our Diabetes article.

Peripheral Neuropathy (Polyneuropathy)
This is a general diagnosis used to describe when there are a large number of nerves affected by neuropathy in the peripheral nervous system. The peripheral nervous system is made up of all of the nerves of the body, located outside of the brain and spinal cord. They consist of two main types, namely motor nerves that send signals to the muscles to allow for movement, and sensory nerves, which allow us to sense touch, vibration, and pain. Peripheral neuropathy is a descriptive (or labelling) diagnosis, meaning that it only functions to describe a grouping of symptoms and does not actually give us any information on the underlying cause. There can be a number of different underlying causes of peripheral neuropathy, and at the moment, this condition is not well understood by the medical community. The most common symptoms of peripheral neuropathy are a combination of muscle weakness (motor nerves), and loss of sensation (sensory nerves). Some people may also experience tingling, numbness and pain (particularly burning or shooting pain). The location of the symptoms will depend on the particular nerve or nerve group affected.

Autonomic Neuropathy
In rare cases, the autonomic nerves can be affected and can cause problems with a number of involuntary body functions. Symptoms can include: fluctuations in heart rate, blood pressure, and perspiration. Other symptoms of this condition can be varied and may include: loss of bladder control, abdominal pain, difficulty swallowing, nausea, vomiting, hypoglycemia, fecal incontinence, diarrhea, constipation, and dizziness on standing.

TREATMENT

Treat the Root
The correct treatment method for neuropathy is always directed at the underlying cause as much as possible. Please see above for more information. Removing offending toxins, drugs, and infections are an essential first step in treatment. In general, boosting and regulating the immune response can help prevent autoimmune problems and promote the clearing of any viral or bacterial infections contributing to symptoms. For more information, please see our Immune System article. Maintaining appropriate blood glucose control in diabetics and remedying any nutritional deficiencies are also essential.

Physical Therapy
In cases of single neuropathies, it is essential to isolate and treat any trauma and to perform physical therapy to promote healthy posture and take pressure off of any nerves compressed by structural problems. Ergonomics for everyday activities are also essential to reduce repetitive strain injuries. Avoid cramped positions, and those that can cause unnecessary pressure on your extremities, such as crossing legs and arms for prolonged periods.

Diet and Lifestyle
It is essential to quit smoking entirely. Be sure to maintain a diet filled with fruits and vegetables and maintain a regular exercise program. Staying active helps to prevent muscle loss over time. Be mindful when you are moving if you have loss of sensation, and do a body check each morning and night, paying particular attention to the feet and hands for signs of injury. If injury occurs, be sure to seek immediate medical attention, as loss of proper pain sense can prevent you from knowing how serious an injury is, or if an infection has occurred. Massaging your feet and hands, or having others give you massage is another great way to stimulate a return of proper sensation and blood flow.

Symptom Management
To treat the numbness, tingling and pain associated with neuropathy many healthcare practitioners will recommend capsaicin (Cayenne based) cream. This creates a very warm sensation on the skin initially, but with continued use can block pain signals in the nerves and help reduce pain sensations. Electrical nerve stimulation is also commonly used to treat the symptoms of neuropathy. Transcutaneous electrical nerve stimulation (TENS) machines can help to block pain transmission pathways. With these devices, adhesive electrodes are placed in specific locations on the skin and a gentle electric current is delivered at varying frequencies to alleviate pain symptoms. Acupuncture has also been shown to reduce symptoms in 75% of peripheral neuropathy cases, especially with repeated treatments over time. Electro-stimulation can be combined with acupuncture treatment to further increase benefit (electroacupuncture). Ask your healthcare provider for more information.