US Pharm. 2018;43(3):13-14.

Reactivated Chickenpox

Shingles is an illness caused by the varicella-zoster virus, the same virus that causes chickenpox. Although people recover from the symptoms of chickenpox, the virus remains inactive in the body, hidden in the nerve cells near the spinal cord and brain. Sometimes, for unknown reasons, the virus reactivates and travels along the nerves to the skin, where it causes a painful, itchy, blistery rash known as shingles. The rash typically heals in 2 to 4 weeks; however, the associated pain can last for months. Only people who previously had chickenpox develop shingles, but there is a vaccine to reduce the risk.

Chickenpox Comes First, Then Shingles

Shingles occurs in over 1 million people each year. Approximately half of all cases occur in people over age 60 years, but it can also affect children with a history of chickenpox. Since the virus is more likely to reactivate in individuals with a weakened immune system, older adults and people with HIV/AIDS, lymphoma, or leukemia are at greatest risk. The likelihood of shingles is also higher in people taking medications that suppress the immune system, such as chemotherapy or steroids, or medications taken after an organ transplant.

Most of the time, shingles begins with pain, burning, or tingling sensations and sensitivity, usually on one side of the body, but also around the eye or neck.  Within a few days, the blistery rash appears in a band-like pattern following the nerve path. The rash begins as small, itchy bumps that fill with fluid, break open, and crust over into scabs. The area usually heals without scarring unless it becomes infected. Shingles can also cause fever, headache, fatigue, and sensitivity to light.

Prompt Diagnosis Helps

To diagnose shingles, the physician considers the physical symptoms, the patient’s health history, and laboratory tests. Individuals diagnosed with shingles can spread the virus and cause chickenpox in those who have never had chickenpox or its vaccine. They cannot spread chickenpox to those who have already had it, since shingles occurs only when the dormant chickenpox virus reactivates.

There is no cure for shingles. However, antiviral medications such as acyclovir, famciclovir, or valacyclovir taken within 72 hours of symptom onset can shorten the duration of the illness, reduce the severity of symptoms, and decrease the risk of complications.

In addition to antiviral medications, soaking in a cool bath, taking an oatmeal bath, or using calamine lotion may help relieve the pain and itching of shingles and speed healing of the blisters. Other drugs that may be helpful in controlling the pain include capsaicin, numbing agents such as lidocaine, steroids, antidepressants, and anticonvulsants.

Potential Complications

Most people recover from shingles without complications. However, when complications arise, they can be serious. The shingles rash can become infected due to scratching and may require treatment with antibiotics. If the rash is near the eyes or ears, vision damage or hearing loss can result. Another serious complication of shingles is postherpetic neuralgia, a sharp or throbbing pain under the skin that remains after the rash has healed. Postherpetic neuralgia can cause pain so severe that it hurts to have clothes touching the skin. The older the person is when shingles develops, the greater the chance for postherpetic neuralgia to develop. This nerve pain can last for months or even years, making routine activities difficult, which can cause depression.

Preventive Measure

Since it is impossible to predict whether the varicella-zoster virus will reactivate, the best way to prevent shingles is vaccination. There are two vaccines: Zostavax and Shingrix, a new, more effective one that became available in 2017. The CDC recommends Shingrix for all adults aged 50 years and older—even those previously vaccinated with Zostavax. People with a history of shingles should also consider vaccination because the virus can reactivate more than once. Talk to your pharmacist to find out if vaccination is right for you.

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