A range of medications that act on the central nervous system has been found to be useful in managing neuropathic pain. Commonly used treatments include tricyclic antidepressants (such as nortriptyline or amitriptyline), the serotonin-norepinephrine reuptake inhibitor (SNRI) medication duloxetine, and antiepileptic therapies such as gabapentin, pregabalin, or sodium valproate. Few studies have examined whether nonsteroidal anti-inflammatory drugs are effective in treating peripheral neuropathy.

Symptomatic relief for the pain of peripheral neuropathy may be obtained by application of topical capsaicin. Capsaicin is the factor that causes heat in chili peppers. The evidence suggesting that capsaicin applied to the skin reduces pain for peripheral neuropathy is of moderate to low quality and should be interpreted carefully before using this treatment option. Local anesthesia often is used to counteract the initial discomfort of the capsaicin. Some current research in animal models has shown that depleting neurotrophin-3 may oppose the demyelination present in some peripheral neuropathies by increasing myelin formation.

High-quality evidence supports the use of cannabis for neuropathic pain.

The treatment of peripheral neuropathy varies based on the cause of the condition, and treating the underlying condition can aid in the management of neuropathy. When peripheral neuropathy results from diabetes mellitus or prediabetes, blood sugar management is key to treatment. In prediabetes in particular, strict blood sugar control can significantly alter the course of neuropathy. In peripheral neuropathy that stems from immune-mediated diseases, the underlying condition is treated with intravenous immunoglobulin or steroids. When peripheral neuropathy results from vitamin deficiencies or other disorders, those are treated as well.

When an underlying medical condition is causing the neuropathy, treatment should first be directed at this condition. For example, if weight gain is the underlying cause, then a weight loss program is the most appropriate treatment. Compression neuropathy occurring in pregnancy often resolves after delivery, so no specific treatment is usually required. Some compression neuropathies are amenable to surgery: carpal tunnel syndrome and cubital tunnel syndrome are two common examples. Whether or not it is appropriate to offer surgery in any particular case depends on the severity of the symptoms, the risks of the proposed operation, and the prognosis if untreated. After surgery, the symptoms may resolve completely, but if the compression was sufficiently severe or prolonged then the nerve may not recover fully and some symptoms may persist. Drug treatment may be useful for an underlying condition (including peripheral oedema), or for ameliorating neuropathic pain.

Capsaicin applied to the skin in a 0.075% concentration has not been found to be more effective than placebo for treating pain associated with diabetic neuropathy. There is insufficient evidence to draw conclusions for more concentrated forms of capsaicin, clonidine, or lidocaine applied to the skin.

As above, the serotonin-norepinephrine reuptake inhibitors (SNRIs) duloxetine and venlafaxine are recommended in multiple medical guidelines as first or second-line therapy for DPN. A 2017 systematic review and meta-analysis of randomized controlled trials concluded there is moderate quality evidence that duloxetine and venlafaxine each provide a large benefit in reducing diabetic neuropathic pain. Common side effects include dizziness, nausea, and sleepiness.

One review found that antivirals (such as aciclovir) are ineffective in improving recovery from Bell's palsy beyond steroids alone in mild to moderate disease. Another review found a benefit but stated the evidence was not very good to support this conclusion.

In severe disease it is also unclear. One 2015 review found no effect regardless of severity. Another review found a small benefit when added to steroids in those with severe disease.

They are commonly prescribed due to a theoretical link between Bell's palsy and the herpes simplex and varicella zoster virus. There is still the possibility that they might result in a benefit less than 7% as this has not been ruled out.

A nerve may be compressed by prolonged or repeated external force, such as sitting with one's arm over the back of a chair (radial nerve), frequently resting one's elbows on a table (ulnar nerve), or an ill-fitting cast or brace on the leg (peroneal nerve). Part of the patient's body can cause the compression and the term "entrapment neuropathy" is used particularly in this situation. The offending structure may be a well-defined lesion such as a tumour (for example a lipoma, neurofibroma or metastasis), a ganglion cyst or a haematoma. Alternatively, there may be expansion of the tissues around a nerve in a space where there is little room for this to occur, as is often the case in carpal tunnel syndrome. This may be due to weight gain or peripheral oedema (especially in pregnancy), or to a specific condition such as acromegaly, hypothyroidism or scleroderma and psoriasis.

Some conditions cause nerves to be particularly susceptible to compression. These include diabetes, in which the blood supply to the nerves is already compromised, rendering the nerve more sensitive to minor degrees of compression. The genetic condition HNPP is a much rarer cause.

Steroids have been shown to be effective at improving recovery in Bell's palsy while antivirals have not. In those who are unable to close their eyes, eye protective measures are required.

The mechanism of axonal degeneration has not been clarified and is an area of continuing research on alcoholic polyneuropathy.

Further research is looking at the effect an alcoholics’ consumption and choice of alcoholic beverage on their development of alcoholic polyneuropathy. Some beverages may include more nutrients than others (such as thiamine), but the effects of this with regards to helping with a nutritional deficiency in alcoholics is yet unknown.

There is still controversy about the reasons for the development of alcoholic polyneuropathy. Some argue it is a direct result of alcohol's toxic effect on the nerves, but others say factors such as a nutritional deficiency or chronic liver disease may play a role in the development as well. This debate is ongoing and research is continuing in an effort to discover the real cause of alcoholic polyneuropathy.

No definite standard treatment have been set. This is because treatments of the disease has been poorly studied as of 2014. Often in cases of inflammatory parenchymal disease, "corticosteroids should be given as infusions of

intravenous methylprednisolone followed by a slowly tapering course of oral steroids". It is suggested that therapy should be continued for a period of time even when the symptoms get suppressed because early relapse may occur. Sometimes, the medical doctors may suggest a different steroid depending on the nature of the disease, the severity, and the response to steroids. According to several studies, parenchymal NBD patients successfully suppress the symptoms with the prescribed steroids. As for non-parenchymal patients, there is no general consensus on how to treat the disease. The reason is that the mechanisms of cerebral venous thrombosis in BD are still poorly understood. Some doctors use anti-coagulants to prevent a clot. On the other hand, some doctors only give steroids and immunosuppressants alone.

Painful dysesthesias caused by alcoholic polyneuropathy can be treated by using gabapentin or amitriptyline in combination with over-the-counter pain medications, such as aspirin, ibuprofen, or acetaminophen. Tricyclic antidepressants such as amitriptyline, or carbamazepine may help stabbing pains and have central and peripheral anticholinergic and sedative effects. These agents have central effects on pain transmission and block the active reuptake of norepinephrine and serotonin.

Anticonvulsant drugs like gabapentin block the active reuptake of norepinephrine and serotonin and have properties that relieve neuropathic pain. However, these drugs take a few weeks to become effective and are rarely used in the treatment of acute pain.

Topical analgesics like capsaicin may also relieve minor aches and pains of muscles and joints.

In one study of 387 Behçet's disease (BD) patients that has been done for 20 years, 13% of men with BD developed to NBD and 5.6% of women developed to NBD.

Combining all statistical reports, approximately 9.4% (43 of 459) BD patients advanced to NBD. In addition, men were 2.8 times more likely to experience NBD than women. This fact indicates possible gender-based pathology.

In speaking about age of NBD patients, the general range was between 20 and 40. NBD patients with age less than 10 or more than 50 were very uncommon.

Modulating and ameliorating diabetic complications may improve the overall quality of life for diabetic patients. For example; when elevated blood pressure was tightly controlled, diabetic related deaths were reduced by 32% compared to those with less controlled blood pressure.

Many observational and clinical studies have been conducted to investigate the role of vitamins on diabetic complications,

In the First National Health and Nutrition Examination Survey (NHANES I) Epidemiologic Follow-up Study, vitamin supplementations were associated with 24% reduction on the risk of diabetes, observed during 20 years of follow-up.

Many observational studies and clinical trials have linked several vitamins with the pathological process of diabetes; these vitamins include folate, thiamine, β-carotene, and vitamin E, C, B12, and D.

- "Vitamin D:"

Vitamin D insufficiency is common in diabetics. Observational studies show that serum vitamin D is inversely associated with biomarkers of diabetes; impaired insulin secretion, insulin resistance, and glucose intolerance.

It has been suggested that vitamin D may induce beneficial effects on diabetic complications by modulating differentiation and growth of pancreatic β-cells and protecting these cells from apoptosis, thus improving β-cells functions and survival. Vitamin D has also been suggested to act on immune system and modulate inflammatory responses by influencing proliferation and differentiation of different immune cells., Moreover, deficiency of vitamin D may contribute to diabetic complications by inducing hyperparathyroidism, since elevated parathyroid hormone levels are associated with reduced β-cells function, impaired insulin sensitivity, and glucose intolerance. Finally, vitamin D may reduce the risk of vascular complications by modulating lipid profile.

- "Antioxidants" may have beneficial effects on diabetic complications by reducing blood pressure, attenuating oxidative stress and inflammatory biomarkers, improving lipid metabolism, insulin-mediated glucose disposal, and by enhancing endothelial function.

Vitamin C has been proposed to induce beneficial effects by two other mechanisms. It may replace glucose in many chemical reactions due to its similarity in structure, may prevent the non-enzymatic glycosylation of proteins, and might reduce glycated hemoglobin (HbA1c) levels. Secondly, vitamin C has also been suggested to play a role in lipid regulation as a controlling catabolism of cholesterol to bile acid.

Treatments are generally directed toward stopping the inflammation and suppressing the immune system. Typically, corticosteroids such as prednisone are used. Additionally, other immune suppression drugs, such as cyclophosphamide and others, are considered. In case of an infection, antimicrobial agents including cephalexin may be prescribed. Affected organs (such as the heart or lungs) may require specific medical treatment intended to improve their function during the active phase of the disease.

People with RA have an increased risk of infections and mortality and recommended vaccinations can reduce these risks. The inactivated influenza vaccine should be received annually. The pneumococcal vaccine should be administered twice for people under the age 65 and once for those over 65. Lastly, the live-attenuated zoster vaccine should be administered once after the age 60, but is not recommended in people on a tumor necrosis factor alpha blocker.

The treatment of SLE involves preventing flares and reducing their severity and duration when they occur.

Treatment can include corticosteroids and anti-malarial drugs. Certain types of lupus nephritis such as diffuse proliferative glomerulonephritis require intermittent cytotoxic drugs. These drugs include cyclophosphamide and mycophenolate.

Hydroxychloroquine was approved by the FDA for lupus in 1955. Some drugs approved for other diseases are used for SLE 'off-label'. In November 2010, an FDA advisory panel recommended approving belimumab (Benlysta) as a treatment for the pain and flare-ups common in lupus. The drug was approved by the FDA in March 2011.

There are established epigenetic and environmental risk factors for RA. Smoking is an established risk factor for RA in Caucasian populations, increasing the risk three times compared to non-smokers, particularly in men, heavy smokers, and those who are rheumatoid factor positive. Modest alcohol consumption may be protective.

Silica exposure has been linked to RA.

Treatment is targeted to the underlying cause. However, most vasculitis in general are treated with steroids (e.g. methylprednisolone) because the underlying cause of the vasculitis is due to hyperactive immunological damage. Immunosuppressants such as cyclophosphamide and azathioprine may also be given.

A systematic review of antineutrophil cytoplasmic antibody (ANCA) positive vasculitis identified best treatments depending on whether the goal is to induce remission or maintenance and depending on severity of the vasculitis.

Due to the variety of symptoms and organ system involvement with SLE, its severity in an individual must be assessed in order to successfully treat SLE. Mild or remittent disease may, sometimes, be safely left untreated. If required, nonsteroidal anti-inflammatory drugs and antimalarials may be used. Medications such as prednisone, mycophenolic acid and tacrolimus have been used in the past.

Vasculitis is a group of disorders that destroy blood vessels by inflammation. Both arteries and veins are affected. Lymphangitis is sometimes considered a type of vasculitis. Vasculitis is primarily caused by leukocyte migration and resultant damage.

Although both occur in vasculitis, inflammation of veins (phlebitis) or arteries (arteritis) are their own are separate entities.

Adenocarcinoma of the bowel has been associated with coeliac disease.

Fibromyalgia was found in 9% of adult patients relative to 0.03% in the general population with a link common to IBD. Concurrent IBS is found in 30% to 70%. Small intestinal bacterial overgrowth is associated is common with a transient response to antimicrobial therapy.

The standard treatment for GPA is cyclophosphamide and high dose corticosteroids for remission induction and less toxic immunosuppressants like azathioprine, leflunomide, methotrexate or mycophenolate mofetil. Trimethoprim/sulfamethoxazole may also help prevent relapse. Rituximab may be substituted for cyclophosphamide in inducing remission.

A systematic review of 84 trials examined the evidence for various treatments in GPA. Many trials include data on pooled groups of people with GPA and microscopic polyangiitis. In this review, cases are divided between localised disease, non-organ threatening, generalized organ-threatening disease and severe kidney vasculitis and immediately life-threatening disease.

- In generalised non-organ-threatening disease, remission can be induced with methotrexate and steroids, where the steroid dose is reduced after a remission has been achieved and methotrexate used as maintenance.

- In case of organ-threatening disease, pulsed intravenous cyclophosphamide with steroids is recommended. Once remission has been achieved, azathioprine and steroids can be used to maintain remission.

- In severe kidney vasculitis, the same regimen is used but with the addition of plasma exchange.

- In pulmonary haemorrhage, high doses of cyclophosphamide with pulsed methylprednisolone may be used, or alternatively CYC, steroids, and plasma exchange.

Therapy for GPA and MPA has two main components: induction of remission with initial immunosuppressive therapy, and maintenance of remission with immunosuppressive therapy for a variable period to prevent relapse.

The mainstay of treatment for granulomatosis with polyangiitis (GPA) is a combination of corticosteroids and cytotoxic agents.

- Medications

- Side effect treatments

- Plasma exchange

- Kidney transplant

Before modern treatments, the 2-year mortality was over 90% and average survival five months. Death usually resulted from uremia or respiratory failure.

With corticosteroids and cyclophosphamide, 5-year survival is over 80%. Long-term complications are common (86%), mainly chronic kidney failure, hearing loss and deafness.

Today, drug toxicity is managed more carefully and long-term remissions are possible. Some patients are able to lead relatively normal lives and remain in remission for 20+ years after treatment.