What is neuralgia?
Neuralgia is a stabbing, burning, and often quite severe pain that occurs due to a damaged nerve. The damaged nerve may be anywhere in the body, but it’s most commonly located in the face and neck. The cause of a damaged nerve may be a disease, such as diabetes or multiple sclerosis, an infection, such as shingles, or old age. Treatment for the pain of neuralgia depends on the cause.
Types of neuralgia
Neuralgia can occur in different parts of the body and can have various causes. Oftentimes, the cause for this pain is unknown.
This type of neuralgia occurs as a complication of shingles and may be anywhere on the body. Shingles is a viral infection characterized by a painful rash and blisters. Neuralgia can erupt wherever the outbreak of shingles occurred. It can be mild or severe, and persistent or intermittent, and it can last for months or years. In some cases, the pain may occur before the rash. It will always occur in the distribution of one nerve — usually isolated to one side of the body.
This type of neuralgia is associated with pain from the trigeminal nerve, which travels from the brain to the face. The pain can be caused by a blood vessel pressing down on the trigeminal nerve where it meets with the brainstem. It can also be caused by multiple sclerosis. Trigeminal neuralgia causes severe, recurrent pain in the face, usually on one side. It’s most common in the elderly.
Pain from the glossopharyngeal nerve, which is in the throat, is not very common. This type of neuralgia produces pain in the neck and throat.
Causes of neuralgia
The underlying cause of any type of neuralgia is damage to a nerve. Each nerve in your body is protected by a coating called the myelin sheath. When the myelin is damaged or wears away from the nerve, the stabbing, severe, shock-like pain of neuralgia results. There are many different factors — including old age — that can cause damage to the myelin. Unfortunately, in many cases of neuralgia a cause can never be found.
The cause of postherpetic neuralgia is shingles, an infection caused by the chickenpox virus. The likelihood of having this infection increases with age. People with Lyme disease, HIV, and syphilis also have a higher incidence of neuralgias, though neuralgia is not a common manifestation of any of these diseases.
Multiple sclerosis (MS) is a disease that is caused by the deterioration of myelin. MS causes many symptoms; one of them is neuralgia in the face.
Pressure on nerves
The myelin on nerves can be worn away by pressure. The pressure may come from something that is pressing on the nerve such as a:
- blood vessel
The pressure of a swollen blood vessel is a common cause in trigeminal neuralgia.
Many people with diabetes will suffer from some type of neuralgia because excess glucose in the bloodstream can lead to myelin damage.
Less common causes
If the cause of neuralgia isn’t infection, MS, diabetes, or pressure on the nerves, it may be from one of many less-common factors. These include:
- chronic kidney disease
- porphyria, a rare blood disease
- medications such as cisplatin, paclitaxel, or vincristine (prescribed to cancer patients)
- trauma, such as that caused by surgery
- chemical irritation
When to seek medical help
The pain of neuralgia is usually very severe and can be debilitating. If you experience such pain, you should see your doctor as soon as possible, especially when the pain is not helped by over-the-counter medications.
You should also see your doctor if you suspect you have shingles. In addition to the pain of neuralgia, shingles causes a red, blistering rash. It is usually on the back or abdomen, but may also be on the neck and face. Shingles should be treated as soon as possible to prevent post-infectious complications, such as postherpetic neuralgia, which can cause debilitating lifelong pain.
What to expect at a doctor’s appointment
When you see your doctor for neuralgia, you can expect to be asked a series of questions about your symptoms. Your doctor will want you to describe the pain and to tell them how long the pain has been a problem. You will also need to inform your doctor of any medications you are taking and of any other medical issues you have. This is because neuralgia may be a symptom of another disorder like diabetes, MS, or shingles.
Your doctor will also perform a physical exam to pinpoint the location of the pain and, if possible, the nerve causing it. You may also need to have a dental exam. If the pain is in your face, your doctor may want to rule out other possible dental causes, such as an abscess. An abscess is a bacterial infection of the tooth that causes a very painful toothache, along with other unpleasant symptoms like pus and tissue swelling. Left untreated, it can lead to extremely serious, life-threatening complications.
To find an underlying cause of your pain, your doctor may order certain tests. You may need to have blood drawn to check your blood sugar levels and kidney function. A magnetic resonance imaging (MRI) test can help your doctor determine if you have MS. A nerve conduction velocity test can show the speed at which signals are moving through your nerves; this test helps to determine nerve damage.
Treatment of neuralgia
If your doctor is able to pinpoint the cause of neuralgia, your treatment will focus on the underlying cause. If the cause is not found, treatment will focus on relieving your pain.
Potential treatments may include:
- surgery to relieve the pressure on the nerve, which could be caused by blood vessels, bones, ligaments, or tumors
- better control of blood sugar levels in those with diabetes-caused neuralgia
- physical therapy
- nerve block, which is an injection directed at a particular nerve or nerve group that is intended to “turn off” pain signals and reduce inflammation
- medications to relieve the pain
Medications prescribed may include:
- over-the-counter pain relievers like aspirin or ibuprofen
- antidepressants like amitriptyline or nortriptyline, which are effective in treating nerve pain
- antiseizure medications like carbamazepine, which is effective for trigeminal neuralgia
- narcotic pain medications for the short-term like codeine
- topical creams with capsaicin
Outlook for neuralgia
There is no cure for neuralgia, but treatment can help improve your symptoms. Some types of neuralgia improve over time. One example is postherpetic neuralgia caused by shingles. More research is being done to develop better treatments for neuralgia.