What is Small Fiber Neuropathy?
Small Fiber Neuropathy (SFN) is a condition that affects the smallest
nerves in your body. These tiny nerve fibers control how you feel pain,
temperature, and touch. When they don't work properly, you might experience
burning pain, tingling, numbness, or strange sensations in your hands and feet.
SFN is more common than many people realize, with the lowest estimates guessing around 200K
people in the United States alone. It's often seen in people with diabetes, autoimmune conditions, or certain
genetic factors. The good news is that with proper diagnosis and treatment,
many people with SFN can find relief and maintain a good quality of life.
Understanding your condition is the first step toward feeling better.
The sections below will help you learn about the different aspects of SFN,
from what causes it to how it's treated. Remember, you're not alone in this
journey, and there are many resources and treatments available to help you.
Causes
Small Fiber Neuropathy can have many different causes. The most common
cause is diabetes, which damages nerves over time through high blood sugar
levels. However, many other conditions can lead to SFN, including autoimmune
diseases, vitamin deficiencies, and genetic factors.
In about half of all SFN cases, doctors can't find a specific cause.
This is called "idiopathic" SFN, which simply means the cause is unknown.
Even when the cause isn't clear, effective treatments are still available
to help manage symptoms and improve quality of life.
Understanding what might have caused your SFN can help guide treatment
decisions. Sometimes treating the underlying cause can slow down or even
improve neuropathy symptoms. Learn more about SFN causes
Diagnosis
The most definitive test for SFN is a skin biopsy, where tiny samples
of skin are examined under a microscope to count small nerve fibers. Blood
tests help identify possible causes like diabetes or vitamin deficiencies.
Other tests might include quantitative sensory testing and autonomic function tests.
While the diagnostic process can be frustrating, getting the right
diagnosis is important for finding effective treatments. Working with a
neurologist who understands SFN can make a big difference.
Learn more about SFN diagnosis
Symptoms
SFN symptoms are often described as burning, stabbing, or tingling
sensations. Many people say it feels like walking on hot coals or being
stuck with pins and needles. These symptoms usually start in the feet and
hands and can gradually spread throughout the entire body.
Common symptoms include burning pain, numbness, sensitivity to touch,
and difficulty sensing temperature changes. Some people also experience
problems with automatic body functions like sweating, digestion, or blood
pressure changes.
Symptoms can vary greatly from person to person and may change over time.
Some people have mild symptoms that come and go, while others have constant
pain that affects daily activities. Understanding your symptoms helps you
and your healthcare team develop the best treatment plan.
Learn more about SFN symptoms
Treatments
While there's no cure for SFN yet, many treatments can help manage
pain and improve quality of life. Treatment usually involves a combination
of medications, lifestyle changes, and other therapies. The goal is to
reduce symptoms and treat any underlying conditions that might be causing
the neuropathy.
Common medications include anticonvulsants like gabapentin and pregabalin,
antidepressants like duloxetine, and topical treatments like lidocaine patches.
Supplements such as alpha-lipoic acid and B vitamins may also help. Lifestyle
changes like regular exercise, good blood sugar control, and stress management
play important roles too.
Finding the right treatment takes time and patience. What works for one
person might not work for another, so doctors often try different combinations
until they find what works best. The sooner treatment begins, the better
the chances of managing symptoms effectively.
Learn more about SFN treatments
Written by the SFN Foundation
August 20, 2025
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