Peripheral neuropathy is one of the most common diagnoses handed out with no cause attached. Numbness, tingling, or burning in the feet is easy to label and harder to explain. Explaining it is the job, because the cause decides whether the nerves can recover.
What is peripheral neuropathy?
Neuropathy means nerve disease. Peripheral says which nerves: the network outside the brain and spinal cord that carries sensation in, sends movement out, and quietly runs heart rate, sweating, blood pressure, and digestion. Paresthesia is the medical word for the tingling and pins and needles it produces.
Damage there causes numbness, tingling, burning, or weakness. It nearly always starts in the feet, because the nerves reaching the toes are the longest in the body and fail at the far end first. The hands are usually involved only once the legs are affected to about the knee. Our article on neuropathy in the feet covers that first stage in detail.
Visual guide
The jobs of peripheral nerves
- Sensation: Sensory nerves carry touch, temperature, and pain information.
- Movement: Motor nerves help muscles move.
- Automatic functions: Autonomic nerves help regulate internal body functions.
Types of peripheral neuropathy
The pattern of the damage is the first clue to the cause, and identifying it is most of what the examination is for.
| Pattern | What it looks like | Common examples |
|---|---|---|
| Mononeuropathy | One nerve, at one spot where it is squeezed | Carpal tunnel, ulnar nerve at the elbow |
| Polyneuropathy | Many nerves at once, both sides, feet first | Diabetes, alcohol, chemotherapy, CIDP |
| Small fiber | Burning pain with normal strength and reflexes | Diabetes, Sjögren's, long COVID, idiopathic |
| Autonomic | Lightheadedness standing, sweating, bladder and gut changes | Diabetes, amyloidosis, autoimmune disease |
| Motor-predominant | Weakness and wasting ahead of numbness | CIDP, Guillain-Barré, inherited neuropathies |
Anatomy at a glanceNerves beyond the spine
A closer look at the nerves in your feet
Peripheral nerves connect the spinal cord with the skin, muscles, and other tissues.
Peripheral nerves
These nerves carry messages between the spinal cord and the rest of the body.
Sensory nerve endings
Fine nerve endings help you feel touch, temperature, and pain.
Feet-first pattern
Many neuropathies cause symptoms in the toes and feet first. Other patterns are possible.
The pattern of symptoms helps guide which nerves and causes to investigate.
Simplified peripheral nerve anatomy with an enlarged detail. Nerve branches and symptom patterns vary.
Small fiber neuropathy
This is the pattern most often missed. The small fibers carry pain and temperature and run the sweat glands and blood vessels, so damage to them produces burning, stabbing, and sensitivity to touch with normal strength and normal reflexes. Nerve conduction studies test only the large fibers, so people with burning feet are often told their nerve tests are normal. A skin biopsy counts the small nerve endings in the skin directly and settles it; our article on how accurate the biopsy is explains what a result does and does not tell you.
Proximal neuropathy
Most neuropathy is distal, meaning feet first. Proximal neuropathy affects the hip, buttock, and thigh instead, usually on one side, with pain followed by weakness and wasting of the thigh. The usual cause is diabetes, in which case it is called diabetic amyotrophy. It is uncommon, most often affects older adults whose diabetes was not thought to be severe, and generally improves over months to years. It needs a different workup from feet-first neuropathy.
Neuropathy in the head or face
The cranial nerves are peripheral nerves too, so neuropathy can affect the face: Bell's palsy is a neuropathy of the facial nerve, and trigeminal neuralgia involves the nerve that carries facial sensation. "Brain neuropathy" is not a medical term. The brain is central, not peripheral, and numbness that comes from the brain or spinal cord, as in multiple sclerosis, is a different problem with different tests; our neuropathy vs MS article goes through the differences.
Peripheral neuropathy symptoms
- Numbness and tingling in the toes, spreading slowly upward
- Burning, stabbing, or electric pain, often worse at night
- Sensitivity to touch, so that socks or bedsheets hurt
- Weakness or clumsiness, tripping, or muscle twitching
- Unsteadiness, particularly in the dark
- Autonomic symptoms: lightheadedness on standing, altered sweating, bladder or digestive trouble
What neuropathy feels like varies with the fibers involved: cotton wool under the feet, walking on pebbles, a tight sock that is not there, or feet that burn at night and feel like ice by day.
When neuropathy is an emergency
Numbness or weakness spreading over days rather than months, especially with trouble walking, breathing, or swallowing, can be Guillain-Barré syndrome. That belongs in an emergency department the same day.
Causes of peripheral neuropathy
Finding the cause is the point of the workup: it decides the treatment and the outlook.
| Cause | Clue that points to it | Can the nerves recover? |
|---|---|---|
| Diabetes or prediabetes | The most common cause; raised blood sugar or A1c | Often stabilizes, sometimes improves, with control |
| Vitamin B12 deficiency | Long-term acid reducers or metformin, anemia | Often, if treated early |
| Alcohol | Years of heavy use with poor nutrition alongside | Partly, once drinking stops |
| Medications and toxins | Began after chemotherapy, or a heavy-metal exposure | Usually improves slowly once it stops |
| Autoimmune, inflammatory | Faster or stepwise course, weakness, asymmetry | Yes, and this is where treatment changes most |
| Thyroid, kidney, liver disease | Abnormal routine blood work, swelling, fatigue | Usually, as the underlying disease is treated |
| Infection | Lyme, shingles, HIV, hepatitis C, sometimes after COVID | Often, once the infection is treated |
| Hereditary | High arches, hammer toes, family history, lifelong | No, but braces and therapy keep people walking |
Pressure on a single nerve or a nerve root is a different problem with a different workup. And in a meaningful share of cases no cause is found even after a thorough search. That is idiopathic neuropathy: usually sensory, slow, and treatable as a symptom. It is a conclusion to reach after the search, not instead of it.
Diagnosing peripheral neuropathy
- History and examination decide everything that follows. Testing light touch, pinprick, vibration, and position sense separately identifies the pattern.
- Blood tests cover the treatable causes: blood sugar and A1c, B12, thyroid, kidney and liver function, protein abnormalities, autoimmune markers.
- Nerve conduction studies and EMG show how well the large fibers conduct, and where. Most useful with weakness, asymmetry, or suspected inflammation.
- Small fiber skin biopsy for burning pain with normal nerve conduction studies.
- Occasionally more: spine MRI, a lumbar puncture for suspected CIDP, or genetic testing when the story is lifelong.
Peripheral neuropathy treatment
Treatment runs on two tracks at once, and they are not interchangeable.
Treating the cause stops further damage: blood sugar control, replacing a missing vitamin, stopping the drug responsible, or immune treatment such as intravenous immunoglobulin for an inflammatory neuropathy. Nerves regenerate slowly and often incompletely, which is the argument for finding the cause early. Whether a given neuropathy can be reversed depends on that cause; our article on whether neuropathy can be reversed goes through the types one by one.
Treating the symptoms runs in parallel, because nerve pain does not wait. Ordinary painkillers work poorly for it. The classes a neurologist considers are the anti-seizure medications used for nerve pain, such as gabapentin and pregabalin, and certain antidepressants, such as duloxetine and the older tricyclics, which relieve nerve pain independently of any effect on mood. Topical capsaicin or lidocaine suits a small painful area. Which one, and how it is started, is an individual decision made with you.
Practical measures matter as much as prescriptions. Physical therapy for balance, and a brace for foot drop, prevent falls. Numb feet do not report injuries, so daily foot checks and good shoes prevent the wounds that cause real trouble.
Visual guide
Care starts with the cause
- Cause: Diabetes, deficiencies, and other causes need targeted care.
- Symptoms: Pain treatment can help even when nerve damage persists.
- Protection: Foot care and attention to balance help prevent complications.
When to see a neurologist
See one if symptoms have lasted more than a few weeks, are spreading, come with weakness, or were labelled neuropathy with no cause attached.
Dr. Achillefs Ntranos, MD sees neuropathy patients in Beverly Hills and Los Angeles, and by video across California. A first visit is 60 minutes, mostly history and examination. We do not perform nerve conduction studies or EMG in our office; when they are needed we arrange them nearby and review the results with you. Skin biopsy is done at our Beverly Hills office, with the sample analyzed by Therapath. You can request a visit in Beverly Hills or Los Angeles, or by video anywhere in California.
Neuropathy in the feet
Why it starts in the feet, and what the pattern says about the cause.
Can neuropathy be reversed?
Which types improve with treatment, and which do not.
Frequently asked questions
References
- National Institute of Neurological Disorders and Stroke. Peripheral neuropathy.
- Cleveland Clinic. Peripheral neuropathy: what it is, symptoms and treatment.
- Johns Hopkins Medicine. Peripheral neuropathy.
- Foundation for Peripheral Neuropathy. Treatments.
- National Institute of Diabetes and Digestive and Kidney Diseases. Diabetic neuropathy.
- American Academy of Neurology. Oral and Topical Treatment of Painful Diabetic Polyneuropathy: Practice Guideline Update Summary. Neurology, 2022.