Shingles and Nerve Paths

Nerve Paths That Shingles Follow: Dermatomes and Herpes Zoster

Updated December 4, 2023

In nature, we've seen time and again that what can appear chaotic and random at first glance often has a hidden order. From the seeds of a sunflower following the Fibonacci sequence to the spiral of the nautilus shell flawlessly reflecting the Golden Ratio, nature is full of patterns based on some unseen logic.

This also extends to our bodies.

For example, skin rashes and breakouts can seem to appear at random. But in many cases, they often have underlying patterns. This is the case if you get shingles, a common skin rash that will affect roughly a third of the US population at some point in their lives.

Read on to find out what exactly shingles are, how to prevent them, how to treat them, and to learn the true nature of their deceptively random appearance.

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What Are Shingles?

Shingles, also called herpes zoster, is a viral infection that causes a characteristic skin rash. The virus that causes shingles, the varicella-zoster virus, is actually the same virus that causes chickenpox. After a person recovers from chickenpox, the virus lies dormant in their nervous system. For reasons that are not fully understood, the virus can also reactivate later in life and cause shingles.

Shingles follow nerve paths on arm

When the virus reactivates, shingles usually start with a feeling of tingling or burning on one side of the body or face. After a few days, a rash of small, fluid-filled blisters, similar to when you develop chickenpox, appears on the same side of the body or face. Shingles can even infect the eyes.

Shingles is a painful condition; and these blisters are quite painful and can last for two to four weeks. Eventually, the blisters will scab over and heal, and the rash usually clears within a few weeks.

In the U.S., about a million shingles cases are diagnosed each year. Symptoms of shingles develop in approximately 10% of people who have had chickenpox at an earlier date. The chance of developing shingles increases as you get older, resulting in about half of the cases of shingles occurring in people over the age of 50. For the prevention of shingles, the Center for Disease Control and Prevention (CDC) recommends that people over 50 receive the shingles vaccine Shingrix.

Shingles Infographic

Shingles and Nerves Paths and Dermatomes, Oh My!

While the skin is the most obviously affected organ during a shingles outbreak, the virus actually affects the nervous system of people with shingles as well. The nervous system is made up of the brain and spinal cord (the central nervous system) and the nerves that branch out from them to the rest of the body (the peripheral nervous system).

Nerves are made up of fibers that send signals back and forth between the brain and the rest of the body. These signals control everything from our movement to our sense of touch to our ability to feel pain. In essence, the job of nerves is to relay information.

The human nervous system

To do this, nerves are organized into networks called dermatomes. Dermatomes are areas of the skin that are connected to the nervous system by a single nerve.

This arrangement allows for very specific and refined control over sensation and movement. Conversely, it also means that damage to a specific nerve can result in loss of sensation or function in a very specific area of the skin.

How do shingles affect dermatomes ?

Each half of your body has 31 spinal nerves that function as a communication channel between the spine and the rest of your body. With the exception of the C1 spinal nerve inside your neck, all of these nerves are connected to a dermatome; a spot on your skin where only one spinal nerve sends sensations.

For instance, the right-sided C5 spinal nerve is responsible for transmitting sensory information from the right side's shoulder and collarbone to the spinal cord and brain. In this area, there is only one dermatome affecting the skin.

Nerve paths along the arm

Shingles lesions typically develop around 1 or 2 dermatomes on a body side. Their precise position is a function of the infecting nerve. When the shingles virus targets and infects a particular nerve, the characteristic shingles rash appears as the virus travels along that nerve's dermatome, sort of like a road map.

Shingles following nerve paths along the arm

Because each spinal nerve only sends sensory information to one side of your body, this is why the painful rash does not cross your midline, even on the chest and back.

Additional nerve complications

It's not just shingles lesions that can develop along a dermatome. In some cases, the risk of shingles can also cause more serious nerve damage, which can lead to complications such as:

Harm to the motor nerve

The nerves that aid in muscle movement can also get infected by the herpes zoster virus. Segmental zoster paresis is a disease that is thought to affect 0.5 to 5% of individuals with shingles. The muscles surrounding the shingles rash become weak as a result of this illness.

Harm to the cranial nerve

Cranial nerve

The cranial nerves, one of the main nerves in your brain, can occasionally be impacted by the herpes zoster virus as well. Ramsay Hunt syndrome is a disorder caused by shingles that affects cranial nerve VII (the face nerve) in less than 1% of patients.

Symptoms of this condition include:

  • lateral facial paralysis
  • ear ache
  • ear blisters
  • dry eyes
  • loss of hearing
  • a change in taste
  • vertigo\stinnitus

Long Term Effects

While most people heal within the two to four-week timeframe, some people experience long-term effects from shingles. In a small number of cases, chronic pain associated with shingles can last for months or even years after the initial rash has healed. This complication of shingles is known as postherpetic neuralgia (PHN) and can be extremely debilitating.

Types of meds to treat postherpetic neuralgia pain

A variety of medications

Anticonvulsants

The Food and Drug Administration (FDA) has given the go-ahead for anticonvulsants like gabapentin and pregabalin to treat postherpetic neuralgia. To reduce pain, these medications alter the release of neurotransmitters via binding to calcium channels. This results in a calming effect and can help with nerve pain.

Antidepressants

Many different antidepressants can be used to treat pain in little doses. Tricyclic antidepressants are one kind of antidepressant frequently used for this purpose. These medications prevent serotonin and norepinephrine from being reabsorbed. This, in turn, can help with pain.

However, Tricyclic antidepressants may cause side effects such as:

  • Dry mouth

  • Constipation

  • Urinary retention

  • Weight gain

  • Drowsiness or fatigue

  • Blurry vision

Opioids

Although opioid drugs are useful for treating nerve pain, doctors frequently hesitate to recommend them unless all other treatments have failed. This is because they can cause dependence or overdose. What often starts as a short-term solution can quickly become a long-term problem.

Topical agents

Because the shingles virus obviously affects the skin, topical agents are another popular treatment option.

Lidocaine, an anesthetic, is frequently used as a topical cream for shingles pain. This medication is thought to work by numbing the affected nerve endings.

Capsaicin, the compound that makes chili peppers spicy, is another topical agent that can be used to treat shingles pain. This medication works by depleting substance P, a neurotransmitter that is responsible for sending pain signals to the brain.

While these treatments can be effective, they are not without their side effects. Both Lidocaine and Capsaicin can cause stinging, burning pain, itching and redness. As a potential remedy to relieve pain associated with shingles, these topical agents may wind up causing more irritation than they relieve.

Dermeleve®

Dermeleve® is a topical cream that provides fast and long-lasting relief from the pain and itching associated with shingles cases.

Dermeleve is a safe, fast-acting, long-lasting itch relief solution.

Unlike Lidocaine and Capsaicin, Dermeleve® does not rely on harsh chemicals or irritating ingredients to achieve its goal. Instead, this cream uses a unique blend of natural ingredients like shea butter with skin-healthy vitamins and ceramides.

What sets Dermeleve® apart from other itch relief medications on the market is that it is free of corticosteroids such as hydrocortisone and cortisol, which are associated with some serious side effects to areas of skin exposed to them.

Dermeleve® also works incredibly quickly, providing relief in as little as five minutes as opposed to the days, if not weeks, required by topical steroids. Apart from the inconvenience of having to wait so long for relief with topical steroids, the longer the use the higher the risk of topical steroid withdrawal; a terrible condition that can easily prove worse than the initial treatment the topical steroids were trying to treat in the first place.

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Wrap Up

If you’ve been unlucky enough to develop shingles, hopefully, this article has helped provide some understanding about why and how the rash forms where it does. And while there is no cure for shingles, Dermeleve® can help relieve your symptoms so you can get back to feeling like yourself again.

Visit the Dermeleve® website today to start relieving your shingles symptoms now!

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