Shingles, or herpes zoster, is a reactivation of the varicella-zoster virus, the virus that causes chicken pox. The virus lies dormant in the brain and reappears when the immune system is impaired, commonly in adults older than 50 years old. Symptoms include rash, burning pain, and skin lesions. Complications include encephalitis, eye problems, and a form of chronic pain called postherpetic neuralgia. Treatment with antiviral therapy should begin within 72 hours of rash onset.
Acyclovir
Acyclovir was the initial standard treatment for herpes zoster. The recommended oral dosage is 800 mg five times daily for 7 to 10 days. A 1996 meta-analysis published by Dr. Wood in the journal Clinical Infectious Diseases concluded acyclovir decreased pain duration and prevalence by 50 percent. Nausea and headache are the most common side effects and the dose must be adjusted in patients with impaired kidney function. Acyclovir use has declined because of the dosing frequency and it is poorly absorbed by the body.
Valacyclovir
Valacyclovir is an updated version of acyclovir. Its benefit is that it is absorbed well by the body and requires less frequent dosing. According to a comparison study by Dr. Beutner, published in a 1995 issue of the journal Antimicrobial Agents and Chemotherapy, valacylcovir resolved pain 34 percent faster than acyclovir. The recommended dose is 1000 mg three times daily for 7 days. Nausea and headache are common side effects and the dose requires adjustment in people with impaired kidney function.
Famciclovir
Famciclovir is another antiviral that is readily absorbed by the body and requires less frequent dosing than acyclovir. Both famiciclovir and valacyclovir have similar effectiveness and safety profiles. The recommend dose of famciclovir is 500 mg three times daily for 7 days. Common side effects include headache, nausea, and upset stomach. Dose adjustment is required if used in people with impaired kidney function.
Corticosteroids
Oral corticosteroids, such as prednisone or prednisolone, may be combined with antiviral therapy to reduce pain intensity. Corticosteroids cause numerous side effects, including upset stomach, weight gain, worsening of blood sugar control in persons with diabetes, and swelling. Corticosteroid use is limited because chronic diseases, such as diabetes and high blood pressure, are common in adults over 50 years of age.
References
- "Clinical Infectious Diseases"; Recommendations for the Management of Herpes Zoster; Robert H. Dworkin, et al.; January 2007
- "Journal of the American Academy of Dermatology"; Management of herpes zoster and postherpetic neuralgia; Stephen K. Trying; December 2007
- "Clinical Infectious Diseases"; Oral acyclovir therapy accelerates pain resolution in patients wtih herpes zoster: a meta-analysis of placebo-controlled trials; Wood, et al; 1996
