Patient education: Shingles (Beyond the Basics)

SHINGLES OVERVIEW — Shingles, also known as herpes zoster, is a painful rash caused by varicella-zoster virus (the same virus that causes chickenpox).

After a person has had chickenpox, the virus continues to reside in the body, causing no symptoms. Later in life, it can become active again, causing the shingles rash. The term "shingles" comes from the Latin word "cingulum," which means belt or girdle; this is because the rash usually appears in a band or belt-like pattern.

Shingles can affect people of all ages. It is particularly common in adults over age 50 years. It is also more common in people of all ages with conditions that weaken the immune system.

Varicella-zoster virus belongs to a group of viruses called "herpesviruses." Other viruses in this group include herpes simplex virus, which causes cold sores and genital herpes. (See "Patient education: Genital herpes (Beyond the Basics)".)

RISK OF SHINGLES — Up to 20 percent of people will develop shingles during their lifetime. The condition occurs in people who have had chickenpox in the past. Occasionally, a person can develop shingles without knowing they have had chickenpox before.

Age — Shingles can occur in people of all ages, but it is much more common in adults 50 years of age and older.

Immune status — Shingles can occur in healthy adults. However, some people are at a higher risk of developing shingles because of a weakened or "compromised" immune system. The immune system, which normally helps your body fight infection, can be weakened by:

●Certain cancers or other diseases that interfere with the body's normal immune response

●Chemotherapy to treat cancer

●Immune-suppressing medications used to treat certain conditions (such as rheumatoid arthritis) or to prevent rejection after an organ transplant

●Infection with HIV, the virus that causes AIDS

SHINGLES SIGNS AND SYMPTOMS — Shingles usually begins with unusual sensations such as itching, burning, or tingling feelings in an area of skin on one side of the body. Some people also develop a fever, a generalized feeling of being unwell, or a headache. Within one to two days, a rash of blisters appears on one side of the body in a band-like pattern (picture 1A-B).

The shingles rash most commonly affects the trunk (chest, abdomen, and back) (figure 1). However, the rash can show up on almost any part of the body. If a rash develops near the eye, it can permanently affect the vision if left untreated. (See 'Eye complications' below.)

The pain of shingles can be mild or severe and usually has a sharp, stabbing, or burning quality. Pain may begin several days before the rash appears. Pain is limited to the parts of the skin affected by the rash, but it can be severe enough to interfere with daily activities and sleep. Pain is often worse in older adults than in younger people.

Within three to four days, the shingles blisters can become open sores or "ulcers." In individuals with a healthy immune system, the sores crust over and are no longer infectious by days 7 to 10, and the rash generally disappears within three to four weeks. Scarring and changes in skin color may persist long after shingles has resolved.

In most cases, shingles runs its course without any lasting health problems. However, the condition can be associated with complications, which are described below.

Is shingles contagious? — It is not possible to catch shingles from another person.

However, if you have never had chickenpox or the chickenpox vaccine, you can get chickenpox from someone who has shingles. This can happen after direct (skin-to-skin) contact with a shingles blister or, rarely, by breathing in the varicella-zoster virus through the air. For this reason, if you have never had chickenpox (or the vaccine to prevent it), you should generally avoid being near anyone with the shingles rash. Let your health care provider know if you think you may have been exposed.

Similarly, if you have shingles, you should avoid contact with people who have never had chickenpox or the chickenpox vaccine. (See "Patient education: Chickenpox prevention and treatment (Beyond the Basics)".)

SHINGLES COMPLICATIONS — Complications of shingles can occur in anyone but are more likely in older adults and in people with a weakened immune system (eg, people who have had an organ transplant or people who have HIV and a low CD4 count).

Postherpetic neuralgia — This is a term used to describe pain that lasts for more than three months after the onset of the shingles rash. It is the most common complication of shingles. The pain typically affects the areas of skin that were affected by the rash; it can be mild to severe and is often described as "burning." Postherpetic neuralgia affects 10 to 15 percent of people, with about half of these cases occurring in individuals older than 60 years.

In most cases, the pain of postherpetic neuralgia gradually improves over time. Some people continue to experience pain for months to years after the rash resolves. This pain can be so severe that it causes difficulty sleeping, weight loss, and depression and interferes with normal daily activities. Several treatments are available to both prevent and treat postherpetic neuralgia. (See 'Treatment of postherpetic neuralgia' below.)

Skin infection — The sores of shingles can become infected with bacteria, which can delay healing. This complication occurs in about 2 percent of cases. (See "Patient education: Skin and soft tissue infection (cellulitis) (Beyond the Basics)".)

Eye complications — Eye complications occur in about 2 percent of cases. They are much more likely to occur when the shingles rash affects the skin near the eye. Potential complications include eye inflammation (called herpes zoster ophthalmicus) and damage to the retina (called acute retinal necrosis).

These complications are serious and can lead to vision loss, especially if not treated promptly with antiviral medications. Tell your health care provider immediately if you have shingles blisters near your eye or other symptoms such as eye pain or sensitivity.

Ear inflammation — Herpes zoster can cause inflammation of the ear (called herpes zoster oticus or Ramsay Hunt syndrome). Symptoms include weakness of the facial muscles on the affected side, ear pain, and blisters inside the ear canal. It is usually treated with an antiviral medication plus a steroid.

SHINGLES TREATMENT — Treatment of shingles usually includes a combination of antiviral and pain-relieving medications. The areas affected by the rash should be kept clean and dry. In general, it is best to avoid applying lotions or creams (eg, moisturizer) to the affected area, as this can further irritate the skin.

Antiviral medications — Antiviral medications stop the virus from multiplying, help the rash to heal more quickly, and reduce the severity and duration of pain.

Antiviral treatment should be started as soon as possible, as it is most effective when started within 72 hours after the shingles rash appears. After this time, antiviral medications may still be helpful if new blisters are appearing.

Three antiviral drugs are used to treat shingles:

●Acyclovir (brand name: Zovirax)

●Famciclovir (brand name: Famvir)

●Valacyclovir (brand name: Valtrex)

Valacyclovir is most commonly used, although acyclovir is the least expensive treatment. Acyclovir must be taken more frequently than the other drugs (five times daily as opposed to three times daily). Antiviral treatment typically lasts for one week.

Pain medications — The pain related to shingles can be severe, and medications are frequently needed. Nonsteroidal anti-inflammatory drugs (eg, ibuprofen [sample brand names: Advil, Motrin] and naproxen [sample brand names: Aleve, Anaprox]) or acetaminophen (brand name: Tylenol) may help with mild pain. If your pain is severe enough to disrupt sleep, your doctor may prescribe a stronger medication.

Antibiotics — If the rash becomes infected, you may need treatment with an antibiotic medication.

Treatment of postherpetic neuralgia — Treatment is available to reduce pain and maintain quality of life in people with postherpetic neuralgia (see 'Postherpetic neuralgia' above). Treatment generally begins with a medication used to prevent seizures. If that doesn't work, a low-dose tricyclic antidepressant and/or topical treatment may be used. On occasion, prescription opioid medications may be prescribed temporarily.

Anti-seizure medications — Medications that are traditionally used to prevent seizures, called anticonvulsants, can sometimes reduce the pain of postherpetic neuralgia. Anticonvulsants commonly used for postherpetic neuralgia include gabapentin (sample brand name: Neurontin) and pregabalin (sample brand name: Lyrica).

Tricyclic antidepressants — Tricyclic antidepressants (TCAs) are commonly used to treat the pain of postherpetic neuralgia. The dose of TCAs is typically much lower than that used for treating depression. It is believed that these drugs reduce pain when used in low doses, but it is not clear how the drug works.

TCAs used to treat pain include amitriptyline, desipramine, and nortriptyline. It is common to feel tired when starting a TCA; this is not always an undesirable side effect, since it can help improve sleep when the medication is taken in the evening. TCAs are generally started in low doses, which are increased gradually. The pain-relief benefit may not be seen for three or more weeks. These medications may not be recommended for older adults with heart problems.

Capsaicin — Capsaicin is a substance derived from chili peppers that can help to treat pain. Capsaicin cream (sample brand name: Zostrix) may be recommended to treat postherpetic neuralgia. However, the side effects of the cream (including burning, stinging, and skin redness) are intolerable for up to one-third of patients.

Topical anesthetics — Lidocaine (sample brand name: Xylocaine) gel is a medicine that you can rub into your skin. Products that stick to your skin and release lidocaine are also available (eg, Lidoderm, which is a skin patch). You can wear these on your skin for up to 12 hours per day. They deliver a small amount of lidocaine, which helps to numb your skin, to the most painful or itchy areas. However, the benefit of lidocaine is likely to be moderate at best.

Oral pain medications — A short course of prescription pain medications (opioids) may be recommended if other treatments do not provide enough pain relief.

Steroid injections — For people with postherpetic neuralgia who have severe pain despite using the above measures, an injection of steroids directly into the space around the spinal cord may be an option. Steroid injections are not used to treat facial pain.

RETURNING TO WORK — If you have shingles, you may wonder when it is safe to return to work. The answer depends on where you work and where your rash is located:

●If the rash is on your face, do not return to work until the area has crusted over, which generally takes 7 to 10 days.

●If the rash is in an area that you can cover (eg, with a gauze bandage or clothing), you may return to work once you feel well.

●If you work in a health care facility (eg, hospital, medical office, nursing home), consult your health care provider about when it is safe to return to work.

PREVENTION OF SHINGLES

Vaccination — You can reduce your chances of developing shingles by getting the shingles vaccine. Vaccination is typically recommended for adults over 50 years of age. In some cases, vaccination might also be recommended for younger adults if their immune system is weaker than normal. If you do develop shingles after receiving the vaccine, your infection may be less severe, and you are less likely to develop postherpetic neuralgia.

The shingles vaccine can cause temporary side effects such as a sore arm; redness or swelling where you got the shot; or fatigue, muscle pain, headache, fever, or nausea. While side effects may be unpleasant, they typically do not last more than two or three days.

Your health care provider can help you decide whether you should get a shingles vaccine.

More information about the shingles vaccine is also available from the United States Centers for Disease Control and Prevention (CDC) website (https://www.cdc.gov/shingles/multimedia/shringrix-50-older.html).

WHERE TO GET MORE INFORMATION — Your health care provider is the best source of information for questions and concerns related to your medical problem.

This article will be updated as needed on our web site (www.uptodate.com/patients). Related topics for patients, as well as selected articles written for health care professionals, are also available. Some of the most relevant are listed below.

Patient level information — UpToDate offers two types of patient education materials.

The Basics — The Basics patient education pieces answer the four or five key questions a patient might have about a given condition. These articles are best for patients who want a general overview and who prefer short, easy-to-read materials.

Patient education: Chickenpox (The Basics)
Patient education: Shingles (The Basics)
Patient education: Neuropathic pain (The Basics)

Beyond the Basics — Beyond the Basics patient education pieces are longer, more sophisticated, and more detailed. These articles are best for patients who want in-depth information and are comfortable with some medical jargon.

Patient education: Genital herpes (Beyond the Basics)
Patient education: Chickenpox prevention and treatment (Beyond the Basics)
Patient education: Skin and soft tissue infection (cellulitis) (Beyond the Basics)

Professional level information — Professional level articles are designed to keep doctors and other health professionals up-to-date on the latest medical findings. These articles are thorough, long, and complex, and they contain multiple references to the research on which they are based. Professional level articles are best for people who are comfortable with a lot of medical terminology and who want to read the same materials their doctors are reading.

Epidemiology, clinical manifestations, and diagnosis of herpes zoster
Diagnosis of varicella-zoster virus infection
Postherpetic neuralgia
Vaccination for the prevention of shingles (herpes zoster)
Treatment of herpes zoster
Varicella-zoster virus infection in pregnancy

The following organizations also provide reliable health information.

●National Library of Medicine

     (www.nlm.nih.gov/medlineplus/shingles.html, available in Spanish)

●Centers for Disease Control and Prevention (CDC)