Shingles (Herpes zoster) is caused by the same virus that causes chickenpox. When we get over chickenpox the virus remains in our nervous system in a dormant state, and can manifest when our immune systems are overwhelmed fighting other diseases, or become weak with age. Shingles can form a rash of blisters, which crust over in about 3 days and heal in 2 to 4 weeks. They are generally located a dermatome, a band like distribution going around one side of the abdomen or face or involving a limb. Some patients describe an excruciating burning pain, while others experience only mild discomfort. Some complain of pain without ever developing a rash. Usually shingles does not cross the midline and stays either in their right or left dermatome.
The earlier antiviral treatment is started, the more effective. The best time to treat shingles is less than 72 hours from the beginning of signs and symptoms. This is when the medication is most effective, when the viral particles are reproducing, although treatment is sometimes given after 72 hours when new lesions are still appearing, because this likely means that viral reproduction is still ongoing. Once the lesions have developed crusts, antiviral therapy is of little or no benefit and should not be routinely prescribed.
Antiviral medications appear to be most effective in patients older than 50 years of age, in whom the pain usually lasts longer. Efficacy in younger patients is not yet well known.
In the absence of complications, oral medications known as nucleoside analogs are the antiviral agents of choice. Nucleoside analogs are similar to molecules found in viral DNA. Taking the place of normal nucleosides, they prevent the viral DNA from reproducing, so that no new viral particles can be made. This halts the infection. Valacyclovir, famciclovir, and acyclovir can be prescribed. The first two are usually preferred because less frequent doses are needed. Efficacy is equal according to early studies. Doses for each agent are:
- Valacyclovir–1000mg three times per day for 7 days
- Famciclovir–500mg three time per day for 7 days
- Acyclovir–800mg five times per day for 7 days
Complicated Zoster
The most common complication of shingles is postherpetic neuralgia, which can be extremely painful and seriously debilitating for weeks or even years.
Depending on the nerve involved, Zoster can also lead to blindness, hearing difficulties, encephalitis, and kidney disease are rare complications.
Prevention of Shingles
The Centers for Disease Control and Prevention (CDC) recommends recombinant zoster vaccine, (RZV, Shingrix) to prevent herpes zoster in adults 50 years of age or older. It is available from your pharmacist without a prescription.
How to Obtain a Prescription for Shingles?
Antiviral medications are prescription drugs, available with the approval of a physician or other licensed prescriber. QuickMD can treat your herpes zoster and prescribe any of the above medications online.