Herpes zoster medical therapy


 * L. Katie Morrison, MD; Associate Editor(s)-In-Chief:

Treatment


Currently, there is no cure available for Herpes zoster, nor a treatment to effectively eliminate the virus from the body. However, there are some treatments that can mitigate the length of the disease and alleviate certain side effects.

Antiviral drugs
Acyclovir (an antiviral drug) inhibits replication of the viral DNA, and is used both as prophylaxis (e.g., in patients with AIDS) and as therapy for herpes zoster. Other antivirals are valacyclovir and famciclovir. During the acute phase, oral acyclovir should be given. Use of acylovir is most effective in moderating the progress of the symptoms, and in preventing post-herpetic neuralgia, if started within 24 to 72 hours of the onset of symptoms, so medical care should be obtained as soon as the condition is recognized. Immunocompromised patients may respond best to intravenous acyclovir. In patients who are at high risk for recurrences, an oral dose of acyclovir, taken twice daily, is usually effective. It is also reported that the amino acid lysine inhibits the replication of herpes zoster.

Other drugs
Cimetidine, a common component of over-the-counter heartburn medication, has been shown to lessen the severity of herpes zoster outbreaks in several different instances. This usage is considered an off-label use of the drug. In addition, cimetidine and probenecid have been shown to reduce the renal clearance of aciclovir. The study showed these compounds reduce the rate, but not the extent, at which valaciclovir is converted into aciclovir. Renal clearance of aciclovir was reduced by approximately 24% and 33% respectively. In addition, respective increases in the peak plasma concentration of acyclovir of 8% and 22% were observed. The authors concluded that these effects were "not expected to have clinical consequences regarding the safety of valaciclovir". Due to the tendency of aciclovir to precipitate in renal tubules, combining these drugs should only occur under the supervision of a physician.

Complementary Therapies
Digestive Enzymes are available on prescription and in some over the counter preparations. Before the availability of antivirals, oral pancreatic enzyme therapy in shingles was used in some countries and later subjected to clinical and scientific research. A large scale multi-centre clinical study, using an oral preparation of such enzymes, has shown promising results. The results of another clinical study support the concept that oral enzyme therapy is beneficial in diseases characterized in part by TGF-beta overproduction that included shingles patients. TGF-β has also been found to be elevated in instances of VZV infection.