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Health Information
Shingles -
(Herpes Zoster)
En Español (Spanish Version)
Definition
Shingles is a
painful infection of the nerves and skin
caused by the varicella zoster virus. This
is the same virus that causes chickenpox.
Causes
Shingles occurs
in people who have already had chickenpox.
It is considered a reactivation of the
dormant varicella zoster virus. After
causing the initial chickenpox infection,
the virus does not leave the body. Instead,
it settles in the nerve roots near the
spinal cord. Once reactivated, the virus
travels along the nerve paths to the skin.
There it produces pain and rash.
Risk Factors
A risk factor is
something that increases your chance of
getting a disease or condition.
- Age: 50 or
older
- Compromised
immune system, as in:
- People
infected with HIV
-
Patients with lymphoma or leukemia
- Excessive
fatigue
- Physical or
psychological stress
- Radiation
therapy
Most cases of
shingles occur in individuals with no known
risk factor other than age.
Shingles cannot
be transmitted from one person to another.
However, contact with a person who has
shingles could lead to chickenpox in someone
who has never had chickenpox and has not
received the varicella vaccine.
Symptoms
Symptoms
include:
- Rash:
- Appears
as a red, slightly raised band or
patch often overlain with multiple
small fluid-filled blisters
-
Develops on one side of the body or
the other, but typically does not
cross the midline
- In
severe cases may spread to multiple
parts of the body —the so-called
“disseminated” zoster
-
Blisters usually dry out and crust
over within several days
- Most
commonly affects the torso and face
- In severe
cases, the eyes may be affected, which
can seriously threaten vision.
- Pain on the
skin at the site of the rash, which is
usually severe
- Tingling or
itchiness on the skin, which may start a
few days before the rash
- Skin in the
affected area is unusually sensitive to
touch
- Fever
- Headache
- Tiredness
The rash usually
disappears within three weeks. In some
patients, however, the pain continues long
after the rash has healed. This complication
is called postherpetic neuralgia (PHN). It
refers to pain that is present in the
affected area for months, or even years
afterward. The pain of PHN is difficult to
treat and can be very severe.
Diagnosis
The doctor will
ask about your symptoms and medical history,
and perform a physical exam. Usually the
rash can be diagnosed by its appearance. In
very rare situations fluids are drawn from
the
blisters and sent to a lab for
diagnosis.
Treatment
Like any viral
condition, shingles cannot be cured.
Treatment, therefore, is focused on
alleviating symptoms, speeding recovery, and
preventing PHN.
Itch and Pain Relief
Itching may
be relieved by:
-
Calamine lotion
- Wet
compresses
-
Frequent oatmeal baths
Over-the-counter pain relievers include:
- Oral
medications like acetaminophen
(Tylenol), ibuprofen (Advil), and
naproxen (Aleve)
-
Capsaicin, a substance originally
derived from hot peppers, can be
applied topically
Prescription
drugs may be given to help relieve pain
that doesn't respond to over-the-counter
remedies.
Antiviral Drugs
Certain
antiviral medications may help control
shingles by hindering reproduction of
the virus in the nerve cells. They
include:
-
Acyclovir (Zovirax)
-
Famciclovir (Famvir)
-
Valacyclovir (Valtrex)
Antiviral
therapy may shorten the course of an
episode of shingles, but only if started
within 48-72 hours after symptoms first
develop. These medications can also
reduce the severity and duration of PHN
and are generally recommended in
patients at highest risk for this
condition (ie, over 55).
Steroids
A short
course of oral steroid medication (eg,
prednisone) may also be prescribed in
patients whose immune system is
functioning normally.
Postherpetic Neuralgia
Taking
antiviral medications before PHN
develops is the most effective way to
reduce its severity.
A variety of
other treatments are available to help
as well:
-
Capsaicin—topical ointment may also
be useful for PHN
-
Tricyclic antidepressants—typically
prescribed in doses lower than those
needed to treat depression. An SSRI
(selective serotonin reuptake
inhibitor) may also be prescribed.
-
Lidoderm patch—a transdermal form of
lidocaine (a local anesthetic), in
which the medication is gradually
absorbed across the skin
-
Gabapentin—an anti-seizure
medication also useful in the
treatment of PHN
-
Transcutaneous electrical nerve
stimulation (TENS)—a device that
generates low-level pulses of
electrical current and applies it to
the skin's surface
- Nerve
blocks—these are injections near
nerves that may be used to provide
temporary pain relief (usually used
as a last resort)
Prevention
There is no
proven way to prevent an outbreak of
shingles, although undue stress and fatigue
may contribute to an outbreak. Future cases
of shingles should theoretically diminish as
more children avoid chickenpox by receiving
the varicella vaccine.
The US Food and
Drug Administration recently approved a
vaccine (Zostavax) for people over 60 who
have had chickenpox, to help decrease the
likelihood of getting shingles and to
decrease severity if shingles does occur.
RESOURCES:
National Institute of Neurological Disorders
and Stroke
www.ninds.nih.gov
VZV Research Foundation (for research on
Varicella Zoster)
www.vzvfoundation.org
CANADIAN RESOURCE:
Canadian Family Physician
www.cfpc.ca
Public Health Agency of Canada
www.phac-aspc.gc.ca
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