Treatment

Can Herpes Simplex Be Treated?
Many of us are accustomed to taking antibiotics or other medications that will rids us of infection quickly. With virus-caused illnesses, however, a "cure" sometimes is not possible, and infections can linger for long periods. Herpes simplex virus has a complicated life cycle that enables it to persist within the body.

The virus can be attacked, however, with medications called antiviral drugs. While these can't rid the body of HSV, they help many people with herpes control the infection and keep symptoms to a minimum. Antiviral drugs can be taken daily in small doses to prevent herpes symptoms or can be taken in larger doses when signs and symptoms appear.

For many years, people diagnosed with genital herpes had to cope with recurrent symptoms without the benefit of any medications able to target herpes itself. Beginning in 1985, however, the advent of antiviral medication in pills, capsules, or liquid formulations gave patients new options for gaining a measure of control over the infection. Today, a decade later, therapeutic options have expanded yet again, with two new antiviral agents reaching the market. Anyone whose quality of life is significantly affected by genital herpes should talk with a doctor about medication to control outbreaks and minimize the discomfort.

Treatment Regimens
Anti-herpes medication can help to control the infection in one of three ways:

First episode: A 10-day course of medication can dramatically lessen the severity of a first episode. With medication, sores heal faster, other symptoms such as swollen glands are reduced, and viral shedding is ended more quickly.

Episodic Therapy: Taken at the first warning sign of an outbreak, medication can help to shorten the duration of symptoms and speed healing of sores. Relief is not as dramatic as in first episodes, however. Most likely to benefit from episodic therapy are people who have severe or prolonged recurrences and those who experience prodrome. Gains are much greater if therapy is started before herpes lesions appear. In some cases, the prompt use of medication during prodrome will abort the episode before herpes lesions form. Episodic therapy is most effective when patients have medication on hand and can initiate treatment themselves.

Suppressive Therapy: In order to lessen the chance of recurrences or avert them altogether, patients can take a small dose of antiviral medication every day for long periods of time. Patients on the suppressive regimen usually experience a dramatic reduction in the frequency of symptoms, and in one five-year study, 20 percent of patients had no recurrences at all. Overall in this study, the average number of outbreaks dropped from 13 to fewer than two per year by the end of the first year and one per year by the end of the fifth year. (Many physicians will interrupt suppressive therapy at 12-month intervals to re-evaluate the patient's need for medication.)

In addition, recent research suggests that suppressive therapy brings a 95% reduction in the number of days per year on which sub clinical viral shedding occurs and poses a risk of transmission. Whether suppressive therapy alone can prevent transmission, however, is still a matter of study, and people on suppression are still advised to use other precautions as well.

The Medications
Acyclovir, sold under the brand name Zovirax(R) and now available as a generic, has been the herpes drug of choice for over a decade. Acyclovir disrupts the process by which the virus makes copies of itself and spreads to new cells. Taken by mouth several times a day ("acute therapy"), it dramatically reduces the duration and severity of symptoms during first episodes and can hasten healing during recurrences as well if taken during prodrome. As mentioned earlier, acyclovir also can be used on a twice-daily basis for months at a time to prevent recurrences, a regimen called "suppressive therapy."

Valaciclovir, a prescription drug sold as Valtrex(R), is a new compound that uses acyclovir as its active ingredient but is better absorbed by the body than the original formula. The major advantage of this improved absorption is less frequent dosing--twice daily for episodic therapy. Valtrex is approved for use in treating recurrent genital herpes and will likely be approved as well for first episodes and for suppressive therapy.

Famciclovir, a prescription drug sold as Famvir (R), works by a mode of action similar to acyclovir's but persists for longer periods within the body, thereby requiring less frequent dosing (twice daily for episodic therapy). Like valaciclovir, it is approved for use in treating recurrent genital herpes and will likely be approved as well for first episodes and for suppressive therapy.

Safety Concerns
Acyclovir has been used by more than 30 million individuals in 96 countries and has an outstanding safety record. Large numbers of people have taken it continuously for six or more years, also without serious adverse effects. Acyclovir is even being studied in pregnant women, although the drug is not yet licensed for use in pregnancy outside formal research trials. The Acyclovir in Pregnancy Registry, started over ten years ago, has shown no rise in birth defects or any increase in other problems to date. The newer prodrugs valaciclovir and famciclovir have similar safety profiles.

Drug-resistant strains of herpes have been identified in people with weakened immune systems, such as people with AIDS or those on chemotherapy. It appears that strains of herpes that are abnormal or deficient in certain enzymes are more likely to flourish in immune-compromised people, and these strains also are less likely to respond to therapy with acyclovir, valaciclovir or famciclovir. On the other hand, there has been no increase in drug-resistant strains of herpes in the general population since acyclovir was introduced in 1985, and sensitivity to acyclovir remains high in those taking the drug even for several years.

Vaccines
In addition to the new antiviral therapies listed here, researchers are hard at work on vaccines for herpes. The initial goal of such research is a preventive vaccine that would protect the vaccine recipient from infection if he or she were later exposed to herpes. The same type of vaccines might also provide therapeutic benefit to those already infected by reducing their number of herpes outbreaks.