Shingles and Chickenpox (Varicella-Zoster Virus) - Treatment for Postherpetic Neuralgia

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Side effects include skin rashes, increased risk for infection, headache, dizziness, sleepiness, swelling, and upset stomach. Some people experience visual disturbances, ringing in the ears, agitation, or odd movements when drug levels are at their peak. These side effects may limit their value in older people who are at risk of falling. In general, however gabapentin is safer than tricyclic antidepressants for elderly patients.

Pregabalin. Pregabalin (Lyrica) is similar to gabapentin. Like gabapentin, side effects can include sleepiness and dizziness

Other Anticonvulsant Drugs. The AAN guidelines found insufficient evidence to recommend carbamazepine (Tegretol).

Opioids and Opioid-like Drugs

Opioids. Patients with severe pain that does not respond to tricyclic antidepressants may need powerful painkilling opioid drugs. They may be taken by mouth or delivered through a skin patch. Oxycodone is the standard opioid for PHN. Morphine is also used. Methadone (Dolophine) may also be helpful. A 2005 study found that morphine worked best when combined with the anticonvulsant gabapentin. Constipation, drowsiness, and dry mouth are common side effects of opioids.

Tramadol. Tramadol (Ultram) is a pain reliever that has been used as an alternative to opioids. It has opioid-like properties but is not as addictive. (Dependence and abuse have been reported, however.) It can cause nausea but not severe gastrointestinal problems, as NSAIDs can. Studies suggest it might be very helpful for PHN patients, particularly those with heart problems or other conditions that restrict tricyclic antidepressants.

Other Medical Treatments

Intrathecal Corticosteroid Injections. Epidural (also called intrathecal) injections of corticosteroids are administered within the the tough membrane surrounding the spinal cord. The corticosteroids are sometimes combined with anesthetics. Some older studies indicated that these injections may relieve PHN pain, but this treatment is still under investigation and is not common medical practice. A 2006 study reported that epidural injections may provide slight temporary relief for acute shingles attacks, but they do not prevent PHN.

Antiviral Drugs. Researchers are investigating whether treatment with antiviral drugs may help reduce the pain associated with postherpetic neuralgia. A small 2006 study suggested that a 2-week course of therapy with intravenous acyclovir, followed by 1-month treatment with oral valacyclovir, may help relieve pain.