If you have been following the news in recent years, you may have seen that some parents have been refusing vaccinations for their school-age children. They argue that some of the diseases vaccinated against are not actually dangerous. These parents get together and throw “pox parties” when a child contracts that virus, sharing chickenpox-infected lollipops among young guests to build immunity.
What many of these parents don’t realize is that although chickenpox may not be life-threatening, the effects of contracting the virus can strike later in life and result in painful, chronic conditions. One of these conditions, post-herpetic neuralgia, is a chronic pain condition that occurs as a result of shingles and can be debilitating and very difficult to treat.
Shingles is a painful skin condition caused by the virus herpes zoster.
When a person has chickenpox as a child, the virus is then in their body. As they age, some adults will contract shingles. Shingles is characterized by a rash that develops pustules that ooze when scratched. This rash is different than other rashes because it is painful, even when not touched. With treatment, shingles is generally resolved in three weeks, with the likelihood of another outbreak high.
Twenty percent of shingles sufferers may see their rash disappear but will then go on to develop post-herpetic neuralgia. Post-herpetic neuralgia is a condition that involves the nerves damaged by the shingles virus. In a shingles outbreak, damaged nerves are not able to send signals to the brain, and even though the rash is resolved, the pain remains, generally in the same site of the rash. Burning, stabbing pain is not the only symptom of post-herpetic neuralgia. Symptoms of this condition also include uncontrollable itching, numbness or sensitivity, and muscle weakness.
Physicians have had a hard time coming up with a universal definition of post-herpetic neuralgia but have finally settled on the following: a pain level of three or greater that continues for 120 days after the shingles rash has healed. Doctors conduct patient interviews and ask them to complete a Zoster Brief Pain Inventory (ZBPI). This inventory takes into account symptoms other than pain and is more in-depth that the McGill Pain Questionnaire which is shorter.
People at the highest risk for developing post-herpetic neuralgia are those who contracted chickenpox as a child.
Other risk factors for post-herpetic neuralgia include the following:
- No shingles vaccine. People over the age of 60 who have had chickenpox as children should be vaccinated against shingles. This vaccination is the single best way to prevent shingles and post-herpetic neuralgia.
- Autoimmune disorders. A person with a compromised immune system is less able to combat viruses in general but shingles specifically.
- Age. The older a person is when they contract shingles, the more likely they are to then develop post-herpetic neuralgia.
The most important thing to do to prevent post-herpetic neuralgia is to avoid contracting chickenpox by properly vaccinating children. If it is too late for that, the next best type of prevention is to vaccinate against shingles. In a study of adults 60 or older, adults vaccinated with the vaccination called Zostavax were 51% less likely to contract the shingles virus, and 61% less likely to develop the pain condition, post-herpetic neuralgia, if they did contract shingles. Adults aged 60 to 69 saw the best benefit from the vaccination, and the effects lasted about six years.
If you have already contracted shingles, treatment is aimed at easing the pain, treating the rash, and preventing post-herpetic neuralgia.
To that end, physicians often try several different treatments.
- Pain relievers. Topical creams such as capsaicin cream and lidocaine patches are often effective for immediate relief of pain. Over-the-counter drugs such as ibuprofen and acetaminophen are used for mild pain relief, with prescription opioids used sparingly for stronger pain relief.
- Anti-depressants. Tricyclic anti-depressants have successfully treated the pain caused by post-herpetic neuralgia. Anti-depressants do not work instantly, though, and they may produce side effects such as dry mouth and blurred vision.
- Anticonvulsants. Common seizure medicines have been shown to be effective pain relievers for this condition. Carbamazepin, gabapentin, and phenytoin specifically have been proven to relieve pain from post-herpetic neuralgia in 50% of study participants. These drugs also significantly improved quality of life for patients.
If you went to a pox party as a child, or if you were part of the generation before a universal chickenpox vaccination, shingles may affect you at some point in your life. The Shingles Support Society in London offers excellent information and support for those who suffer from shingles, post-herpetic neuralgia, or both.
Image by Xavi Talleda via Flickr