Antiviral agents are clearly beneficial in the treatment of herpes zoster, but the role of corticosteroids is not as well defined. MacFarlane and colleagues conducted a literature review to determine, in an evidence-based manner, the safety, tolerability and effectiveness of corticosteroids in the treatment of herpes zoster.

Although theoretic concerns have been posed that corticosteroid-induced immunosuppression may cause a patient to be at increased risk of viral dissemination, the authors found that these concerns are not borne out by randomized clinical trials of patients with no underlying immunosuppression.

With regard to the tolerability of these agents, the Collaborative Antiviral Study Group reported that the most frequent adverse effects in patients receiving corticosteroids were nausea, vomiting and hyperglycemia. However, these effects occurred with placebo and antiviral agents as well. Another study demonstrated that patients receiving prednisolone in combination with acyclovir for seven to 21 days had a higher incidence of dyspepsia, edema and flushing compared with patients who received acyclovir alone. The difference, however, was not statistically significant. This study also showed that laboratory abnormalities occurred more frequently in patients receiving corticosteroids, but the values returned to normal after the steroid dosage was tapered. Most clinical trials of the use of cortisteroids, however, have excluded patients with other medical problems, and it is these patients who may be more likely to develop side effects.

One study showed that patients receiving corticosteroids in combination with antiviral agents had a greater reduction in pain at seven and 14 days than did patients receiving antiviral agents alone. However, no significant differences were detected in the incidence or severity of postherpetic neuralgia at six months. The Collaborative Antiviral Study Group found that quality of life in the month following the onset of herpes zoster was improved in patients receiving corticosteroids. While the extreme pain associated with postherpetic neuralgia has led physicians to prescribe corticosteroids for treatment of herpes zoster, the authors found no evidence in the literature that corticosteroids reduce the incidence or duration of postherpetic neuralgia.

The authors conclude that recent clinical trials support the use of corticosteroid therapy in patients with herpes zoster. Combined with antiviral therapy, corticosteroid therapy helps reduce acute zoster pain and improves quality of life in the month following the outbreak. The authors note, however, that clinical trials often excluded patients with concomitant conditions such as hypertension, diabetes, peptic ulcer disease, osteoporosis and renal insufficiency, but they believe corticosteroid therapy is a reasonable approach in the treatment of herpes zoster in patients with well-controlled chronic disease, as long as the chronic conditions are carefully monitored. The cost of a three-week course of tapering corticosteroids is less than $10.