Approximately 500,000 Americans will develop shingles this year. This painful condition will usually clear up over the course of a month. For some people, however, nerve damage from a shingles outbreak can cause chronic pain that lasts for months or even years.
If you've ever had chickenpox, you almost certainly have the potential to develop shingles. After chickenpox symptoms clear up, some of the virus called the Varicella-Zoster virus (VZV) remains in your body, hiding out in the nerve fibers of your dorsal root ganglia. The dorsal root ganglia are bundles of nerves in the spinal cord that allow your skin to communicate with your brain. There are some places within the body that the immune system doesn't patrol, including the nervous system. Because of this, VZV can remain dormant in nerve cells for years without ever being detected. When the virus becomes re-activated (due to immunodeficiency from medications, aging, stress, etc), it is considered the Herpes Zoster virus and causes the condition known as shingles.
Normally during a shingles outbreak the virus will travel along nerve fibers out from the spinal cord and towards the skin. The skin may burn or tingle vaguely before a rash is visible. After 2 to 5 days, small bumps will appear that later turn into fluid filled blisters which burst, crust over, and eventually heal. The entire outbreak usually lasts 4 to 5 weeks.
Anywhere from 10-70% of shingles cases will end with a painful condition called post-herpetic neuralgia, or PHN. Exactly why some people develop PHN while others don't isn't entirely clear. There are several theories as to how it develops. One suggests that nerves which were damaged in the initial shingles outbreak grow back abnormally, causing exaggerated signals to be sent to the brain which are then interpreted as extreme sensitivity or pain. Another theory proposes that the herpes zoster virus creates chronic inflammation within the spinal cord, causing long term nerve damage and scarring.
Those experiencing PHN may feel a sharp and jabbing pain, a deeper ache, or burning. The skin around affected nerves may be itchy or numb. Some notice extreme sensitivity to touch or temperature changes. Rare cases reported muscle weakness or paralysis around the damaged nerve.
Several things can increase the risk for developing PHN. The most common risk factor is age. While rarely seen in patients under 50, approximately 10% of those 50-60 years old develop PHN while almost 40% of those over 60 do. The later in life PHN is experienced the longer it tends to last. It is also suggested that women may be more susceptible to developing PHN. Those who had prodromal symptoms (pain or burning before the shingles outbreak) or a severe outbreak are also more likely to develop PHN.
Treatment for PHN focuses on managing nerve pain and burning, both of which can be soothed inexpensively and naturally. For more information on PHN treatment read some of our other articles about shingles.