How do I know if my rash is caused by shingles?
Shingles (herpes zoster) is an extremely painful skin rash caused by the varicella zoster virus, the same virus that causes chickenpox. In people who have had chickenpox, the virus is never fully cleared from the body; instead, it remains dormant in the nerve tissues. When physical or emotional stresses to the body weaken the immune system, the virus reactivates and spreads along the nerve fibers to the particular area of skin supplied by the involved nerve (called a dermatome). The virus responsible for chickenpox and shingles is a member of the herpesviruses, although it is not the same as the herpes simplex 1 and 2 viruses that cause cold sores and genital herpes, respectively.
Pain, itching, tingling, or burning of the skin often precede the rash in an outbreak of shingles. The blisters that develop resemble the lesions of chickenpox but are concentrated in the area supplied by the involved nerve. Rarely, more than one nerve is involved. Blisters may occur along the entire path of the nerve or only in certain areas supplied by the nerve. As with the blisters of chickenpox, the blisters in shingles eventually burst and begin to crust over and heal. The entire outbreak can last for three to four weeks.
Before the blisters are crusted over, the virus can be spread to anyone who does not have immunity to chickenpox through vaccination or previous infection.
The pain of shingles can be so severe, even before the rash develops, that it mimics dangerous conditions such as appendicitis, kidney stones, or a heart attack, depending upon the location of the nerve that is affected. The appearance of the characteristic rash is usually sufficient to establish the diagnosis of shingles.
What are treatment options for shingles?
Antiviral drugs including acyclovir (Zovirax) and valacyclovir (Valtrex) are sometimes prescribed and can help speed healing time and reduce complications. Steroids or pain medications are sometimes given to help control the pain of shingles. Pain medications can be given topically, like the capsaicin topical patch (Qutenza) or lidocaine (cream, gel, patch, or spray). Oral medications that can help with pain control include certain antiseizure medications such as gabapentin (Neurontin). The tricyclic antidepressants such as amitriptyline have also been shown to help with pain relief in people with shingles. Home remedies can include using cool, moist compresses on affected areas or taking cool baths.
Most people with intact immune systems recover completely from shingles, although recurrences are possible. Since immune function declines with age, older people are most vulnerable to shingles. About half of shingles cases occur in people over 60 years of age. People with weakened immune systems due to cancers, chemotherapy, or HIV infection are also at increased risk for the development of shingles. A shingles vaccine, Zostavax, was approved in 2006. The U.S. Food and Drug Administration in 2017 approved a newer vaccine, Shingrix, as the preferred alternative to the older Zostavax vaccine. While the older Zostavax is a live vaccine given as a single injection, Shingrix is a nonliving vaccine. Shingrix is given in two doses at a two- to six-month interval.
Shingles vaccination is recommended for use in people over 60 years of age and has been shown to reduce the symptoms of shingles, shortening the duration of shingles by three days and reducing the incidence of the painful complication of shingles known as postherpetic neuralgia by at least two-thirds.