From the Guidelines
The most common complication of herpes zoster (shingles) is postherpetic neuralgia (PHN), which is the persistence of sometimes debilitating pain weeks to months after resolution of shingles. This complication is particularly prevalent in older persons, with an estimated 15%--30% of the general population experiencing shingles during their lifetimes 1. Other significant complications include:
- Herpes ophthalmicus, which can lead to blindness
- Dissemination, which might involve generalized skin eruptions, and central nervous system, pulmonary, hepatic, and pancreatic complications
- These severe manifestations are more likely to occur in immunocompromised persons. The risk of these complications highlights the importance of prompt recognition and treatment of shingles, as early antiviral treatment can reduce the severity and duration of acute symptoms and may decrease the risk of developing PHN 1. It is essential to note that varicella-zoster virus can be transmitted from the lesions of patients who have shingles to susceptible contacts, although the risk is lower compared to varicella transmission 1.
From the FDA Drug Label
The most frequent adverse event reported during 3 clinical trials of treatment of herpes zoster (shingles) with 800 mg of oral acyclovir 5 times daily for 7 to 10 days in 323 patients was malaise (11. 5%). The 323 placebo recipients reported malaise (11.1%).
The most likely complications associated with herpes zoster (shingles) include:
- Malaise (11.5% of patients) Other potential complications that may occur with shingles, as reported in the postmarketing experience section, include:
- Neurological symptoms: aggressive behavior, agitation, ataxia, coma, confusion, decreased consciousness, delirium, dizziness, dysarthria, encephalopathy, hallucinations, paresthesia, psychosis, seizure, somnolence, tremors
- Gastrointestinal symptoms: diarrhea, gastrointestinal distress, nausea
- Hematologic and lymphatic disorders: anemia, leukocytoclastic vasculitis, leukopenia, lymphadenopathy, thrombocytopenia
- Hepatobiliary tract and pancreas disorders: elevated liver function tests, hepatitis, hyperbilirubinemia, jaundice
- Renal disorders: renal failure, renal pain (may be associated with renal failure), elevated blood urea nitrogen, elevated creatinine, hematuria
- Skin disorders: alopecia, erythema multiforme, photosensitive rash, pruritus, rash, Stevens-Johnson syndrome, toxic epidermal necrolysis, urticaria
- Special senses disorders: visual abnormalities 2
From the Research
Complications of Shingles
The most likely complications associated with herpes zoster (shingles) include:
- Postherpetic neuralgia (PHN), a condition characterized by persistent pain after the rash has resolved 3, 4, 5, 6
- Ocular involvement, which can lead to rare but serious complications and may require referral to an ophthalmologist 3
- Debilitating pain that can persist for several months or even years after the rash has resolved 3, 4
Factors Increasing the Risk of Complications
Factors that may increase the risk of developing complications from shingles include:
- Decreased immune function due to conditions such as human immunodeficiency virus infection, chemotherapy, malignancies, or chronic corticosteroid use 3
- Increasing age, as herpes zoster and PHN become more common with age 3, 4
Treatment and Prevention of Complications
Antiviral medications such as acyclovir, famciclovir, and valacyclovir may be effective in reducing the duration and severity of shingles, but their effectiveness in preventing PHN is limited 3, 4, 6
- The addition of corticosteroids to antiviral treatment may provide modest benefits in reducing pain and the incidence of PHN 3
- Other treatments such as gabapentin, tricyclic antidepressants, and anticonvulsants may be used to manage neuropathic pain, but their effectiveness in preventing PHN is unclear 5, 7