Treatment of erythema multiforme secondary to herpes simplex by prophylactic topical acyclovir

Treatment of mucocutaneous presentations of herpes simplex virus infections

Infections by herpes simplex virus (HSV) types I and II are diverse and quite frequent. After primary infection, the virus establishes a life-long latency in the sensory ganglia and recrudescences may occur at an unpredictable rate. Recurrent labial and genital herpes infections represent the majority of clinical manifestations of HSV infections. Their management is currently well established using evidence-based medicine data. Primary labial herpes is generally not treated with antivirals in otherwise healthy children, although intravenous aciclovir may be offered in severe primary infections, particularly in the immunocompromised patient. The decision whether or not to treat recurrent labial herpes should be evaluated individually and depends on the frequency and severity of relapses, the impairment of the quality of life, and the cost of therapy. Patients with mild disease may benefit from topical therapy, and those with severe and frequent recurrences may be considered for intermittent or long-term oral antiviral therapy. Primary genital herpes is treated with oral or intravenous antivirals, depending on the severity of the infection and associated symptoms. Recurrent genital herpes can be managed with episodic short courses of oral antivirals in patients whose recurrences are moderate to severe and rare, and have a clear prodrome. Patients with >5 episodes/year, severe recurrences or unrecognisable prodromes may be best managed with long-term suppressive antiviral prophylaxis. HSV is also responsible for a variety of other clinical manifestations, including herpetic whitlow, neonatal infection, disseminated and atypical cutaneous infections, traumatic herpes, eczema herpeticum, and HSV-associated erythema multiforme. HSV infection may also represent a complication following cosmetic procedures of the oro-facial region, surgical and dental interventions, sun exposure and burns. Precise treatment guidelines for these HSV infections are not firmly established.

Recurrent erythema multiforme: clinical features and treatment in a large series of patients

Recurrent erythema multiforme is an uncommon disorder. We have reviewed the clinical features and treatment of 65 patients with this condition. The mean number of attacks per year was six (range 2-24), and the mean duration of the disease was 9.5 years (range 2-36) reflecting its chronicity. The majority of patients had oral mucous membrane involvement (69%). In 46 patients (71%) the condition was precipitated by a preceding herpes simplex virus infection. Acyclovir was found to be the most useful first-line treatment, with 55% of patients deriving benefit from either continuous oral acyclovir or a patient-initiated 5-day oral course at the onset of herpes simplex virus infection. Of those failing to respond to acyclovir, a small proportion responded to dapsone. The most resistant patients (11) were treated with azathioprine, with complete disease suppression in all cases.

Prophylactic chemotherapy with acyclovir for recurrent herpes simplex labialis

The medical literature was reviewed and 11 clinical trials of prophylactic topical or peroral acyclovir for the suppression of recurrent herpes simplex labialis were identified. The results of these trials showed that prophylactic topical acyclovir was mostly ineffective, but that prophylactic peroral acyclovir, in doses ranging from 400 to 1,000 mg/day, reduced the frequency of herpes labialis during treatment by 50-78%. The reduction in the frequency of episodes of herpes labialis with acyclovir prophylaxis is less than the suppressive effect that has been reported for herpes genitalis (50-78% vs. 80-90%). In trials of prophylactic acyclovir for herpes labialis induced by experimental ultraviolet radiation, 26% of induced lesions developed within 48 hours of radiation exposure ("immediate" lesions) and, in contrast to "delayed" lesions that developed 2-7 days post-irradiation, were not suppressed by the antiviral compound. It is proposed that these treatment-unresponsive immediate lesions have an atypical pathogenesis, possibly involving latency of herpes simplex virus in the labial epithelium, and that these may be responsible for the apparent difference between herpes labialis and genitalis in the degree of benefit from prophylactic acyclovir therapy.

Acyclovir. An updated review of its antiviral activity, pharmacokinetic properties and therapeutic efficacy

Acyclovir (aciclovir) is a nucleoside antiviral drug with antiviral activity in vitro against members of the herpes group of DNA viruses. As an established treatment of herpes simplex infection, intravenous, oral and to a lesser extent topical formulations of acyclovir provide significant therapeutic benefit in genital herpes simplex and recurrent orofacial herpes simplex. The effect of acyclovir therapy is maximised by early initiation of treatment, especially in non-primary infection which tends to have a less protracted course than the primary episode. Long term prophylactic oral acyclovir, in patients with frequent episodes of genital herpes simplex, totally suppresses recurrences in the majority of subjects; as with other infections responding to acyclovir, viral latency is not eradicated and pretreatment frequencies of recurrence return after discontinuation of treatment. Caution should accompany the prophylactic use of acyclovir in the general population, due to the theoretical risk of the emergence of viral strains resistant to acyclovir and other agents whose mechanism of action is dependent on viral thymidine kinase. Intravenous acyclovir is the treatment of choice in biopsy-proven herpes simplex encephalitis in adults, and has also been successful in the treatment of disseminated herpes simplex in pregnancy and herpes neonatorium. Intravenous and oral acyclovir protect against dissemination and progression of varicella zoster virus infection, but do not protect against post-herpetic neuralgia. In immunocompromised patients, intravenous, oral and topical acyclovir shorten the clinical course of herpes simplex infections while prophylaxis with oral or intravenous dosage forms suppresses reactivation of infection during the period of drug administration. Ophthalmic application of 3% acyclovir ointment rapidly heals herpetic dendritic corneal ulcers and superficial herpetic keratitis. Thus, despite an inability to eradicate latent virus, acyclovir administered in therapeutic or prophylactic fashion is now the standard antiviral therapy in several manifestations of herpes simplex virus infection, and indeed represents a major advance in this regard. With the exception of varicella zoster virus infections, early optimism concerning the use of the drug in diseases due to other herpes viruses has generally not been supported in clinical investigations.

Acyclovir for recurrent erythema multiforme caused by herpes simplex

Herpes-associated erythema multiforme can be controlled by continuous suppressive treatment with oral acyclovir. Erythema multiforme is not prevented if oral acyclovir is administered after a herpes simplex recurrence is evident and it is of no value after erythema multiforme has occurred. There is some question whether continuous topical treatment with acyclovir to sites of recurrent herpes will sometimes prevent erythema multiforme. Erythema multiforme may be precipitated by orolabial and genital recurrences and by recurrences on skin of the buttocks and other sites. Some herpetic recurrences are associated with erythema multiforme and some are not and episodes of erythema multiforme are not always associated with clinical herpetic recurrences.

Oral acyclovir in the suppression of recurrent non-genital herpes simplex virus infection

In a double-blind, placebo-controlled, cross-over trial in 11 patients suffering eight or more episodes of recurrent non-genital herpes simplex virus (HSV) infection per annum, only two patients experienced a recurrence during treatment with oral acyclovir (200 mg 4 times daily) for up to 12 weeks, compared with nine during placebo treatment (P = 0.016). Although lesion development was effectively suppressed in nine of the patients whilst taking acyclovir, the development of prodromal symptoms, and occasionally erythema, was reported by five. There was no difference between acyclovir and placebo in the time to the next recurrence following completion of treatment. No patient reported any side effects of either placebo or acyclovir therapy. It is believed that this is the first report of any form of oral therapy which is effective in suppressing recurrent non-genital HSV infection in immunocompetent patients.

Phenothiazine--another possible etiologic agent in erythema multiforme. Report of a case

A case report is presented which offers evidence that administration of a phenothiazine drug resulted in erythema multiforme of the oral cavity in a psychotic patient. The condition remissed after discontinuation of the medication.

Acyclovir: an update of the clinical applications of this antiherpes agent

This paper reviews the clinical evaluation of acyclovir in the treatment of herpes-virus infections, predominantly those due to herpes simplex and varicella-zoster viruses. Intravenous, oral and topical acyclovir have been reported to be effective in the therapy of a wide variety of established herpes simplex virus infections and the systemic drug has been shown to be capable of suppressing reactivation of that virus. Although acyclovir has less activity against varicella-zoster virus, infections caused by this agent are also susceptible to intravenous and possibly oral therapy. Clinical efficacy against Epstein-Barr virus and cytomegalovirus infections has not been demonstrated but several studies are currently in progress. Limited evidence of in vivo activity against hepatitis B virus also requires further evaluation. Continued studies on tolerance of the drug in clinical use has confirmed the early promise of this selective antiviral, whilst initial concern about the development of widespread resistance has not been borne out in practice.

Acyclovir. A review of its pharmacodynamic properties and therapeutic efficacy

Acyclovir (aciclovir) is a nucleoside analogue antiviral drug related to cytarabine, idoxuridine, trifluridine and vidarabine. In common with these earlier antivirals, acyclovir is active against some members of the herpesvirus group of DNA viruses. The efficacy of topical acyclovir has been convincingly demonstrated in ocular herpetic keratitis, and in initial and primary initial genital herpes infection, but little or no clinical benefit was seen when non-primary initial genital infections were assessed separately. Acyclovir ointment demonstrated little benefit in recurrent genital herpes but topical acyclovir cream decreased the course of the infection by 1 to 2 days. Orally and intravenously administered acyclovir were beneficial in initial genital herpes infections, and oral therapy shortened the duration of recurrent infections by 1 to 2 days but did not ameliorate pain. In non-immunocompromised patients with recurrent herpes simplex labialis, generally little clinical benefit was seen with the use of topical acyclovir ointment even when therapy was initiated during the prodromal phase, while topical acyclovir cream effected small but significant improvements in the clinical but not the symptomological course of the disease. However, in immunocompromised patients, both intravenous and topical acyclovir shortened the clinical course of herpes simplex virus infections occurring mainly on the lips, oral mucosa and face, and prophylaxis with either oral or intravenous acyclovir suppressed the appearance of recurrent lesions from latent virus for the period of drug administration, but acyclovir did not eradicate latent herpesviruses. In non-immunocompromised patients, intravenous acyclovir was shown to decrease the acute pain of zoster, especially in the elderly, but postherpetic neuralgia was not ameliorated. When immunocompromised patients were studied, intravenous acyclovir inhibited the progression of zoster infections and shortened the healing time and duration of viral shedding in patients with cutaneous disseminated zoster. However, acute and post-herpetic pain were not significantly affected. Well designed controlled studies are underway to establish the efficacy of acyclovir in herpes simplex encephalitis and cytomegalovirus infections in immunocompromised patients, infections due to Epstein-Barr virus, and neonatal herpesvirus infections. Despite some aspects of the drug's use which require further clarification, acyclovir will make a major impact on the treatment of herpesviral infections. Barring unexpected findings with wider clinical use, it will become the agent of choice in several conditions.

Treatment of herpes labialis

Untreated herpes labialis may take up to 10 days or more to heal and antiviral therapy must be initiated early if it is to be effective. Acyclovir ointment has been reported to have an antiviral effect but no clinical benefit and a newer formulation, acyclovir cream, has been developed in an attempt to enhance skin penetration. In placebo-controlled trials, acyclovir cream shortened the duration of lesions significantly and when therapy was started before vesicles developed, the number of lesions aborting was increased significantly. This therapy was well tolerated by most patients. Topical acyclovir offers hope for the successful management of herpes labialis where systemic therapy is considered inappropriate.