November 25, 2011
Dear Mayo Clinic:
I have been diagnosed with shingles of the trigeminal nerve affecting my face. How do I reduce the pain in my head and eye after having shingles?
For most people, the pain from a case of shingles usually fades as the rash disappears. But for some, the pain may linger and become a long-term condition. A variety of treatments may lessen this pain, but the condition can be challenging to treat.
Shingles is a localized form of chickenpox. Once you've had chickenpox, the varicella-zoster virus that caused it remains in your body for the rest of your life. As you grow older, the virus can reactivate. Sometimes this occurs when your body is stressed — because of another infection or due to medications that suppress your immune system, for example. The result is shingles. Because you have some immunity against the virus, rather than getting a full body rash, the rash occurs in areas of skin supplied by the nerve where the virus is reactivated.
Shingles typically involves a bandlike rash on the chest, abdomen or face that is usually quite painful. Most people recover from shingles in a few weeks without other problems, but a small number continue to have severe pain in the same distribution that was irritated when the virus returned. Pain that lasts for three months or more is called postherpetic neuralgia.
The risk of developing postherpetic neuralgia increases with age. The condition is much more common in people 60 and older than in younger people with shingles. The area affected also makes a difference. When shingles occurs on the face, as in your case, the likelihood of postherpetic neuralgia is significantly higher than for other parts of the body.
The first-line treatment for postherpetic neuralgia is usually a prescription skin patch containing the pain-reliever lidocaine. Depending on the situation, a lidocaine cream in combination with other substances, such as aspirin, may be helpful. A new patch approved earlier this year by the Food and Drug Administration that contains the medication capsaicin has also been shown to help reduce postherpetic neuralgia. Lidocaine can be used on the forehead but not in the eye, and capsaicin isn't recommended for use on the face. So, other options will be necessary for your situation.
When lidocaine patches or creams aren't effective or cannot be used, the next step is an oral medication. Several classes of drugs have been shown to be helpful. The first includes anti-seizure medications, such as gabapentin and pregabalin. These medications stabilize abnormal electrical activity in your nervous system caused by injured nerves and interrupt the pain process.
The second class of drugs that can decrease postherpetic neuralgia are antidepressants, such as nortriptyline, amitriptyline, and duloxetine. They block absorption of the neurotransmitters norepinephrine and serotonin into nerve cells, making more of these chemicals available in the brain, which lessens pain.
Finally, pain relievers — ranging from over-the-counter medications such as acetaminophen or ibuprofen to prescription drugs such as opioid analgesics — also are often used to treat postherpetic neuralgia.
If medications aren't enough, procedures such as nerve blocks or steroid injections may help lessen postherpetic neuralgia.
A vaccine to protect against shingles is available. Although it doesn't completely prevent shingles, the vaccine decreases by 50 percent a person's risk of developing the condition. For those who get shingles after receiving the vaccine, their risk of developing postherpetic neuralgia is reduced by two-thirds. Whether they have had shingles or not, the vaccine is recommended for adults age 60 and older.
If pain lasts longer than three months after a case of shingles, talk to your primary care doctor, who can work with you to manage the pain with first-line treatments. If patches, creams or medication don't help, a referral to a pain specialist would be a reasonable next step.
— James Watson, M.D., Neurology, Mayo Clinic, Rochester, Minn.