The term “neuropathy” refers to a disorder or disease of the nerves. This can include sensory numbness, muscle weakness or paralysis, gastric dysfunction, or pain. The pain caused by neuropathy is referred to as neuropathic pain, or nerve pain. There are many different types of nerve pain, divided into categories based on their causes.
The classification of different types of nerve pain is for the convenience of researchers and clinicians. When nerve pain is broken down into categories based on cause, it simplifies the task of understanding each specific type of nerve pain and finding an effective treatment.
The main types of nerve pain include:
Toxic nerve pain is caused by ingestion or exposure to a drug or chemical
A common cause of toxic nerve pain is chemotherapy used for cancer treatment. If chemo is the cause, it’s referred to as chemo-induced peripheral neuropathy (CIPN). Symptoms might include pain, burning, tingling, numbness, or problems with motor skills or bathroom control. Someone suffering from CIPN should inform his or her physician immediately, who might decide to reduce, delay, or stop the treatment causing the problem.
Other potential causes of toxic nerve pain are chemicals like mercury, lead, or thallium. Even alcohol can cause peripheral neuropathy; the loss of motor control and distorted sensations that can accompany alcohol consumption are a form of toxic neuropathy.
Metabolic nerve pain is a result of chemical processes in the body
The most well-known sort of metabolic nerve pain is diabetic peripheral neuropathy, which is caused by the persistently high blood sugar levels that accompany untreated diabetes. Diabetic neuropathy can also manifest as gastric issues, bathroom control problems, or weakness, but the best-known symptoms are pain and numbness, often in the feet. The numbness associated with diabetic neuropathy can be particularly problematic, since wounds on the feet can go unnoticed and untreated.
Metabolic nerve pain can sometimes overlap with toxic nerve pain. For example, the neuropathy caused by alcohol can be classified as metabolic, as well as toxic. There are other types of nerve pain associated with diabetes, too, such as kidney failure, vitamin deficiencies, or thyroid disease.
Nerve pain from trauma occurs after an injury or medical intervention
The symptoms of trauma nerve pain, also called post-traumatic neuropathy, typically begin at the site of the trauma and may radiate outward. Sometimes a scar can be the source of trauma nerve pain, but this can potentially be corrected by surgery. Hypersensitivity, temperature changes, and color changes might accompany trauma nerve pain.
Surgery, stab wounds, blunt trauma, or muscle tears can all result in trauma nerve pain. Complex regional pain syndrome almost always occurs after an injury or medical intervention and is therefore a prime example.
Compressive nerve pain is more commonly called a “pinched nerve”
Compressive nerve pain is a result of pressure on a nerve. This pressure can lead to pain, tingling, numbness, or weakness. Compressive nerve pain can also radiate. Sciatica pain, for example, occurs when pressure is placed on the sciatic nerve. The sciatic nerve begins near the base of the spine and runs down the back of the leg. When the sciatic nerve is compressed, it becomes inflamed and can cause pain that radiates down the buttock and the back of the thigh and knee. Sometimes sciatica pain can even radiate as far down as the calf, foot, and toes.
Rest or non-steroidal anti-inflammatory drugs (NSAIDs) are often enough to relieve compression nerve pain. If the pain persists, though, it’s a good idea to see a doctor, as some extreme cases may require physical therapy, injected medications, or surgery.
Autoimmune nerve pain results from an autoimmune disorder
Some autoimmune disorders cause or are accompanied by neuropathy. Vasculitis, for example, is characterized by inflammation of the blood vessels. When the blood vessels that supply nerves become inflamed, it can lead to vasculitic neuropathy.
In other cases of autoimmune nerve pain, the neuropathy may be caused by antibodies involved with the disorder. Since these types of nerve pain are caused by a malfunction of the immune system, the use of immune therapy medications can often relieve pain.
Infections can sometimes leave lingering pain, which is referred to as infectious nerve pain
Perhaps the most well-known source of infectious nerve pain is the Varicella Zoster virus. This is the virus responsible for chicken pox. When the virus reactivates, it can cause painful rashes and is called shingles. If the pain lingers for a long time after the rash is gone, it’s because of nerve damage from shingles and is called post-herpetic neuralgia.
Other conditions that can lead to infectious nerve pain include lyme disease, HIV, and leprosy. As with some other types of nerve pain, there can be some overlap between infectious nerve pain and other classifications. The pain that accompanies Guillain-Barré syndrome, for instance, is classified as infectious nerve pain because it most often manifests after a viral infection; however, Guillain-Barré is an autoimmune response triggered by infection.
Congenital or hereditary nerve pain results from a congenital abnormality
Congenital nerve pain must be inherited, as in Charcot-Marie-Tooth disease or Fabry disease. Fabry disease is characterized by mutations in a specific gene and is hereditary. These mutations cause a build-up of a particular kind of fat, which damages cells. One of the symptoms of Fabry disease is chronic nerve pain.
Fabry disease is relatively rare, affecting between one in 40,000 and one in 60,000 men, but a more common source of congenital nerve pain is Charcot-Marie-Tooth disease. This disease afflicts one in 2,500 people in the United States and is one of the most common sources of congenital nerve pain.
Have you ever experienced any of these types of nerve pain?
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