Article
Mar 15, 2026
Neuropathic pain: causes, symptoms, and new treatments in research
Understand the causes, symptoms, and treatments of neuropathic pain, including advanced options for pain from diabetes and post-herpetic neuralgia. Also, find out how to participate in clinical trials!
Neuropathic pain is one of the most complex and debilitating chronic conditions of the nervous system. It arises when there is injury, dysfunction, or misunderstanding in peripheral or central nerves, causing persistent pain even in the absence of external stimulus.
Unlike common pains - which originate from inflammations or traumas - neuropathic pain is a direct result of an error in communication between the nerves and the brain, making its treatment challenging and multidisciplinary.
In recent years, medicine has advanced in understanding the mechanisms involved in this type of pain, especially in cases associated with diabetes and herpes zoster.
These two mentioned conditions are the most studied currently in clinical research that seeks new treatments to relieve pain and improve the quality of life for patients. Shall we discuss this further?
What is neuropathic pain?
Neuropathic pain is defined as chronic pain caused by injury or dysfunction in the somatosensory nervous system - the network responsible for sensing and transmitting sensations to the brain. It can affect peripheral nerves, nerve roots, or structures of the central nervous system.
In general, the patient feels burning, tingling, stabbing, numbness, or electrical shocks that persist for weeks, months, or years. Even after treating the original cause, the brain continues to receive incorrect pain signals.
This pain deeply affects quality of life, interfering with sleep, mood, and daily activities. In many cases, treatment requires a combination of medications, physical therapy, psychological support, and more recently, therapies evaluated in clinical research aimed at neuropathic pain.
Types of neuropathic pain
Neuropathic pain can be classified according to the location and type of nerve affected. This differentiation is necessary to choose the appropriate treatment. Continue reading to understand a bit more about the topic!
Mononeuropathies
Neuropathic pain can arise when a single nerve is injured, a condition called mononeuropathy. Common situations include nerve compressions, such as in carpal tunnel syndrome. The patient often feels pain, weakness, and changes in sensitivity in the area innervated by the affected nerve.
This form of neuropathic pain can have acute or gradual evolution, depending on the intensity of the injury and the underlying cause. Diagnosis often involves physical examination and nerve conduction tests, allowing identification of the affected nerve and guiding treatment.
In some cases, mononeuropathies may be associated with metabolic changes, trauma, prolonged compression, or even infectious processes. Early and appropriate approach increases the chances of recovery and pain control.
Plexopathies
Plexopathies involve the injury of multiple nerves in a specific region of the peripheral nervous system, such as the brachial and lumbosacral plexuses. This type of neuropathic pain can be caused by trauma, tumors, or inflammatory processes.
The symptoms include intense pain, loss of strength, and sensory changes over large body areas. Patients with diabetes may also present diabetic plexopathy, characterized by sudden and severe pain, primarily in the lower back and lower limbs.
Diagnosis involves imaging tests and electroneuromyography. Treatment aims to reduce inflammation, control neuropathic pain, and also prevent complications.
Polyneuropathies
Polyneuropathies affect multiple nerves simultaneously, usually symmetrically; while plexopathies occur in only one region, polyneuropathies can occur throughout the body.
The most common cause is diabetes, responsible for about 50% of chronic polyneuropathy cases. This type of neuropathic pain usually starts in the feet and progresses to the legs and hands.
In addition to neuropathic pain, symptoms such as loss of sensation, tingling, and weakness are common. In the long term, there is a risk of ulcers, infections, and even amputations in severe untreated cases.
Medical evaluation and strict control of the underlying disease are necessary to reduce the intensity of neuropathic pain and prevent worsening.
Causes of neuropathic pain
Neuropathic pain can have various origins, but all involve injury or degeneration of nerve fibers. Among the main causes are:
Diabetes mellitus: excess glucose damages the myelin sheath that insulates the nerves.
Viral infections: the herpes zoster virus is one of the most well-known causes.
Traumatic injuries: surgeries and accidents can rupture peripheral nerves.
Autoimmune diseases: the immune system attacks its own nervous tissue.
Oncological treatments: chemotherapy and radiotherapy can cause toxic neuropathies.
Nutritional deficiencies: lack of B-complex vitamins compromises neural function.
Each cause produces a different type of neuropathic pain, with its own intensity and symptoms. Next, we delve into two of the most studied causes. Continue reading to learn about them.
What is the relationship between neuropathic pain and herpes zoster?
Herpes zoster is caused by the reactivation of the varicella-zoster virus, which remains dormant in the body after chickenpox. In some patients, even after the resolution of the infection, the neural injury persists and evolves into post-herpetic neuralgia, one of the most painful types of neuropathic pain.
This condition causes intense neuropathic pain, burning, and hypersensitivity in the affected area, which can last for months or years. Elderly individuals and those with compromised immune systems are at higher risk.
How does herpes zoster cause pain?
The virus damages sensory nerve fibers, leading to changes in the conduction of signals that result in constant or intermittent neuropathic pain. Early treatment with antiviral medication reduces the risk but does not completely eliminate the possibility of evolving into chronic pain.
➔ Do you suffer from neuropathic pain after herpes zoster? Find out how to participate in the Synvia clinical trial. |
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What is the relationship between neuropathic pain and diabetes?
Diabetes is one of the main causes of neuropathic pain, especially in cases of inadequate glycemic control. Diabetic neuropathy primarily affects peripheral nerves and can manifest as pain, altered sensitivity, weakness, and tingling.
This type of neuropathic pain occurs due to cumulative damage to the nerves caused by high glucose levels over the years, resulting in nerve degeneration and alterations in pain signaling pathways.
But what actually increases the risk of diabetic neuropathy?
Poor adherence to diabetes treatment;
Prolonged history of the disease;
High cholesterol;
Smoking and alcoholism.
Prevention of diabetic neuropathy involves strict control of blood sugar levels, proper diet, and, of course, regular medical follow-up.
➔ Do you have neuropathic pain due to diabetes? Click and see how to participate in the Synvia study. |
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Signs and symptoms of neuropathic pain
Before listing the symptoms, it is important to understand that neuropathic pain has specific characteristics and can vary in intensity and frequency.
People with neurogenic pain - another term for pain related to nerves - describe a significant impact on their routine, interfering with sleep, work activities, and emotional well-being.
Here are the main signs and symptoms of neuropathic pain:
Tingling: persistent sensation similar to "pins and needles";
Burning: intense and constant burning;
Electric shocks: sudden and painful episodes;
Numbness: reduced sensation, especially in extremities;
Hypersensitivity to touch: intense pain even with light stimuli;
Muscle weakness: difficulty walking or holding objects.
These symptoms can manifest either individually or in combination, and the progression can be slow and progressive over the years, especially in neuropathic pain associated with diabetes.
Diagnosis of neuropathic pain
The diagnosis of neuropathic pain requires careful clinical evaluation, as it can often be confused with other types of pain, especially musculoskeletal or inflammatory pain.
The process starts with a detailed investigation of symptoms, the patient’s history, underlying conditions (such as diabetes and prior herpes zoster infection), and also specific physical examinations to map sensitivity changes.
During the consultation, the doctor seeks to identify some typical characteristics of neuropathic pain - such as burning, tingling, shocks, and hyperesthesia - and also check its distribution throughout the body.
Recognizing neuropathic pain early is important to avoid its progression to severe chronic pain and functional loss. Therefore, individuals with persistent pain should seek specialized evaluation for diagnosis and initiation of appropriate treatment.
Treatments for neuropathic pain
The management of neuropathic pain is multifactorial and usually requires a combination of pharmacological treatments, physical therapies, and behavioral interventions, as neuropathic pain results from changes in the functioning of the nervous system, not being effectively treated solely with common analgesics.
Treatment tends to be continuous and adjusted according to the evolution of the symptoms presented, as many people live with chronic pain and have variable responses to medications.
Before starting any therapy, the doctor evaluates the cause of the neuropathic pain, the duration of symptoms, comorbidities, and impact on daily life. The goal is to reduce pain intensity, improve functionality, and preserve quality of life.
Moreover, some complementary strategies like physical therapy, psychological support, and patient education increase the effectiveness of treatment and help prevent worsening of the condition.
Treatments for diabetic neuropathic pain
In diabetic neuropathy, the treatment of neuropathic pain involves not only pain control but also rigorous metabolic management. The maintenance of adequate glycemic levels reduces the progression of nerve damage and improves symptoms over time.
Measures such as dietary re-education, regular physical activity, and quitting smoking also play a fundamental role in protecting nerve fibers. In some cases, specific vitamins, such as B vitamins, may be indicated for neural support, depending on laboratory tests.
For patients with significant and refractory pain, advanced therapies and follow-up with a multidisciplinary team may be necessary, including specialists in chronic pain.
Treatments for post-herpetic neuropathic pain
In post-herpetic neuralgia, the nerve injury caused by the varicella-zoster virus can lead to intense and persistent neuropathic pain. Early initiation of antiviral treatment during the herpes zoster outbreak helps reduce the risk of evolving into chronic pain, but does not completely eliminate this possibility.
Additionally, strategies for skin protection and controlled tactile stimuli may be recommended to reduce local hypersensitivity. In resistant cases, interventional therapies and experimental therapeutic resources may offer alternatives for control.
Advanced treatments for neuropathic pain from diabetes or post-herpetic pain
Despite advances in managing neuropathic pain, many patients with diabetic neuropathy or post-herpetic neuralgia still experience persistent pain and exhausting routines even after conventional treatment.
In these cases, advanced therapies and innovative medications emerge as transformative and safe options to minimize patients' pain and restore quality of life.
Participation in a clinical trial represents an opportunity for people living with chronic neuropathic pain refractory to conventional treatments, allowing early access to developing therapies and specialized follow-up.
This integrated approach provides comprehensive support for individuals suffering from pain and directly contributes to scientific advancement in the treatment of neuropathic pain - especially for those seeking new therapeutic options and more consistent relief.
Who can participate in the Synvia neuropathic pain treatment and how to enroll?
The participation in Synvia's clinical studies is intended for individuals living with chronic neuropathic pain related to diabetes or neuropathic pain related to herpes zoster, who have not achieved the necessary comfort with conventional treatments.
The goal of our clinical study is to offer access to innovative and safe therapies, specialized medical follow-up, and comprehensive and continuous health assessment - always adhering to strict scientific and ethical safety standards.
To be eligible for Synvia's clinical study, the participant generally must:
Have a diagnosis of neuropathic pain associated with diabetes or post-herpetic neuralgia;
Present persistent, continuous, or recurrent pain;
Be 18 years or older;
Be willing to participate in consultations, examinations, and periodic assessments during the study;
Not have medical conditions that interfere with the protocol criteria (evaluated individually).
Each participant undergoes a detailed screening process, including clinical interviews, examinations, and medical history evaluations to ensure that the study is safe and suitable for their profile.
Selected participants receive comprehensive support, guidance on treatment, assistance throughout the period, and access to the investigational medication when applicable.
Joining a clinical trial is an opportunity to contribute to the evolution of medicine while seeking relief for neuropathic pain.
If you live with neuropathic pain after diabetes or herpes zoster and have already tried other options, click the button below. Your participation can transform your experience and help other patients in the future.
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REFERENCES:
MSD. Neuropathic Pain – Neurological Disorders. MSD Manual – Professional Version. Available at: https://www.msdmanuals.com/pt/profissional/dist%C3%BArbios-neurol%C3%B3gicos/dor/dor-neurop%C3%A1tica#Etiologia_v1033792_pt
PFIZER. Neuropathic pain. Your Health: Pain and Inflammation. Available at: https://www.pfizer.com.br/sua-saude/dor-e-inflamacao/dor-neuropatica
MARTINS, W. A.; et al. Diabetic neuropathy: updated review. Medical Journal of Minas Gerais, 2020. Available at: https://www.rmmg.org/artigo/detalhes/3928
MSD. Post-herpetic Neuralgia. MSD Manual – Lay Version. Available at: https://www.msdmanuals.com/pt/casa/infec%C3%A7%C3%B5es/infec%C3%A7%C3%B5es-por-herpesv%C3%ADrus/neuralgia-p%C3%B3s-herp%C3%A9tica#Tratamento_v14430992_pt
BARON, R.; et al. Neuropathic Pain: Mechanism-Based Diagnosis and Treatment. The Lancet Neurology, v. 9, n. 8, p. 807–819, 2010. Available at: https://pmc.ncbi.nlm.nih.gov/articles/PMC6104256/