Genital herpes acyclovir

Genital herpes Acyclovir is not a cure for genital herpes. There are no data evaluating whether acyclovir will prevent transmission of infection to others. Avoid contact with lesions, or avoid intercourse when lesions and/or symptoms are present to prevent infecting partners. Genital herpes can also be transmitted in the absence of symptoms. Initiate therapy at the first sign or symptom of an episode. 

The antiviral mechanism of action of acyclovir has been reviewed (72). Acyclovir is converted to the monophosphate in herpes vims-infected cells (but only to a limited extent in uninfected cells) by viral-induced thymidine kinase. It is then further phosphorylated by host cell guanosine monophosphate (GMP) kinase to acyclovir diphosphate [66341 -17-1], which in turn is phosphorylated to the triphosphate by unidentified cellular en2ymes. Acyclovir triphosphate [66341 -18-2] inhibits HSV-1 viral DNA polymerase but not cellular DNA polymerase. As a result, acyclovir is 300 to 3000 times more toxic to herpes vimses in an HSV-infected cell than to the cell itself. Studies have shown that a once-daily dose of acyclovir is effective in prevention of recurrent HSV-2 genital herpes (1). HCMV, on the other hand, is relatively uninhibited by acyclovir. 

Acyclovir (Zovirax) and penciclovir (Denavir) are the only topical antiviral dragp currently available These dragp inhibit viral replication. Acyclovir is used in the treatment of initial episodes of genital herpes, as well as heqies simplex virus infections in immunocompromised patients (patients with an immune system incapable of fighting infection). Penciclovir is used for the treatment of recurrent herpes labialis (cold sores) in adults. 

YT Bryson, M Dillon, G Acuna, S Taylor, JD Cherry, BL Johnson, E Wiesmeier, W Growden, T Greagh-Kirk, R Keeney. Treatment of first episodes of genital herpes simplex virus infection with oral acyclovir. A randomized double-blind controlled trial in normal subjects. N Engl J Med 308 916-921, 1983. 

Oral acyclovir, valacyclovir, and famciclovir are the treatments of choice for outpatients with first-episode genital herpes. Treatment does not prevent latency or alter the subsequent frequency and severity of recurrences. 

Oral acyclovir is useful in the treatment of HSV-1 and HSV-2 infections, such as genital herpes, herpes encephalitis, herpes keratitis, herpes labialis, and neonatal herpes. In initial episodes of genital herpes, oral acyclovir has been found to reduce viral shedding, increase the speed of healing of lesions, and decrease the duration of pain and new lesion formation. Acyclovir appears to be less effective in the treatment of recurrent herpes genitalis but may be used for the long-term suppression of recurrent HSV. 

Intravenous acyclovir is used in the treatment of herpes simplex encephalitis, neonatal HSV infection, and mucocutaneous HSV infection in immunocompromised individuals. Acyclovir ointment is used in the treatment of initial genital herpes but is not effective for recurrent disease. Ophthalmic acyclovir formulations, although not available in the United States, are effective in the treatment of herpes keratoconjunctivitis. 

Famciclovir is indicated for the treatment of acute herpes zoster (shingles) it is at least as effective in reducing pain and healing time. Famciclovir is generally as effective as acyclovir in the treatment of HSV. In immunocompetent patients, famciclovir is approved for the treatment and prophylaxis of recurrent genital herpes. For HIV-infected individuals, famciclovir is approved for the treatment of all recurrent mucocutaneous HSV infections. 

Acyclovir 400 mg PO bid less expensive for chronic suppression of genital herpes... 

Topical acyclovir is substantially less effective than oral therapy for primary HSV infection. It is of no benefit in treating recurrent genital herpes. 

Genital herpes simplex Recurrent infection (2 4 episodes per year) Acyclovir Excellent... 

Perinatal herpes simplex type 2 infection Mothers with primary HSV or frequent recurrent genital HSV Acyclovir Proposed effective... 

Acyclovir is useful in the treatment of herpes. Oral herpes is caused by the herpes simplex virus 1 (HSV-1), and genital herpes is caused by the herpes simplex virus 2 (HSV-2). More than 90 percent of the world s population is infected with the oral herpes virus, though there are many infected people who do not exhibit symptoms. Genital herpes is the most prevalent nondurable sexually transmitted disease. In the United States, there are about 30 million people infected with HSV-2 and an estimated 200,000 to 500,000 new cases each year. 

Acyclovir (ACV) is not a true nucleoside, because the guanine residue is attached to an open-chain structure, but it mimics deoxyribose well enough for the compound to be accepted as a substrate by a thymidine kinase specified by certain herpes-type viruses. The normal thymidine kinase in mammalian cells does not recognize ACV as a substrate, however, so only virus-infected cells convert ACV to its monophosphate. Once the first phosphate has been added, the second phosphate is added by cellular guanylate kinase several other cellular kinases can add the third phosphate. The triphosphate is a more potent inhibitor of the viral DNA polymerases than of cellular DNA polymerases and also inactivates the former but not the latter. The net result is that ACV has been an effective treatment of, and prophylaxis for, genital herpes. Also it can result in dramatic relief of pain associated with shingles caused by reactivation of latent varicella-zoster virus, and has been successful in many patients with herpes encephalitis. 

Oral acyclovir has multiple uses (Table 49-1). In primary genital herpes, oral acyclovir shortens by approximately 5 days the duration of symptoms, the time of viral shedding, and the time to resolution of lesions in recurrent genital herpes, the time course is shortened by 1-2 days. 

Oral famciclovir is effective for the treatment of first and recurrent genital herpes attacks and for chronic daily suppression (Table 49-1). It is also used to treat acute herpes zoster (shingles). In controlled trials in immunocompetent patients with zoster, famciclovir was similar to acyclovir in rates of cutaneous healing but was associated with a shorter duration of postherpetic neuralgia. Comparison of famciclovir to valacyclovir for treatment of herpes zoster in immunocompetent patients showed similar rates of cutaneous healing and pain resolution. However, neither drug decreased the incidence of postherpetic neuralgia. 

Acyclovir Antiviral Genital herpes, herpes infections of the skin, and oral herpes Zovirax 5... 

Oral acyclovir, valacyclovir, and famciclovir are the treatments of choice for outpatients with first-episode genital herpes. Treatment does not prevent latency or alter the subsequent frequency and severity of recurrences. Continuous oral antiviral therapy reduces the frequency and the severity of recurrences in 70% to 90% of patients experiencing frequent recurrences. Acyclovir, valacyclovir, and famciclovir have been used to prevent reactivation of infection in patients seropositive for HSV who undergo transplantation procedures or induction chemotherapy for acute leukemia. 

A large, multicenter, double-blind, randomized, placebo-controUed, parallel-design study showed oral valacyclovir and oral acyclovir equally effective in the self-initiated treatment of recurrent genital herpes infection (Valaciclovir International Study Group). 

Fife KH, et al. Valaciclovir versus acyclovir in the treatment of first-episode genital herpes infection. Results of an international, multicenter, double-blind, randomized clinical trial. The Valaciclovir International Herpes Simplex Virus Smdy Group. SexTransm Dis 1997 24(8) 481-486. 

Parenteral acyclovir is the drug of choice for the treatment of initial and recuiTent mucosal or cutaneous herpes simplex infections in immunocompromised patients and for the treatment of disseminated, neonatal, encephalitic, and severe first episodes of genital herpes simplex infections in immunocompetent patients (Whidey, 1997). Ind avenous acyclovir should also be used for severe diseases such as encephalids (Brady and Bernstein, 2004). 

Kinghorn GR, Woolley PD, Thin RN, De Maubeuge J, Foidart JM, Engst R. Acyclovir vs isoprinosine (immunovir) for suppression of recurrent genital Herpes simplex infection Genitourin Med 1992 68(5) 312-16. 

Tyring SK, Douglas JM Jr, Corey L, Spruance SL, Esmann J. A randomized, placebo-controlled comparison of oral valacyclovir and acyclovir in immunocompetent patients with recurrent genital herpes infections. The Valaciclovir International Study Group. Arch Dermatol I998 134(2) 185-9I. 

Case Conclusion SL is experiencing a recurrent genital herpes outbreak. The treatment of choice is either acyclovir or one of the acyclovir analogues. The duration of symptoms may be shortened because SL was able to identify and seek treatment for her outbreak early. 

Inununosuppressed radiation victims with positive serology for herpes simplex viruses are at risk for reactivation of HSV infection, with resulting clinical picture that mimics radiation stomatitis. These patients should receive prophylaxis with acyclovir or one of its congeners. If serology results are not available, patients with a history of oral or genital herpes infection should receive acyclovir prophylaxis. Patients who develop severe mucositis require assessment for HSV reactivation (2). 

Of the agents available for treatment, acyclovir has had the longest period of use and has not demonstrated an increased risk of birth defects with first-trimester use. More data will need to be collected to strengthen the safety data. Both valacyclovir and famciclovir are newer, and data on safety are more limited. Most women will receive oral acyclovir therapy for first episodes of genital herpes or with recurrence. Intravenous acyclovir can be used for severe infections. 

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