Title Evidence is lacking to recommend 10% n-docosanol versus Penciclovir in treating patients with Recurrent Herpes Labialis (RHL)
Clinical Question Can n-docosanol be used as an alternate to penciclovir for treatment of RHL?
Clinical Bottom Line In patients with RHL, treatment with penciclovir and n-docosanol are better than placebo. However, there is no evidence to suggest that one is better than the other.
Best Evidence  
PubMed ID Author / Year Patient Group Study type
(level of evidence)
11464183 Sacks/2001737 patients with RHL.RCT
Key resultsThis study was conducted across 21 different centers in The United States. All 737 patients presented within 12 hours of noticing initial signs of erythema/prodromal symptoms. The test group used 10% n-docosanol cream, and the control group used polyethylene glycol. At the first visit, the medication was applied in the clinic by the patient and then they were asked to apply it 5 times a day until healing occurred. Test groups showed clinically significant outcomes as compared to placebo: reduction in healing time of all lesions (4.08 days vs. 4.80 days, P=.008), cessation of symptoms (2.18 days vs. 2.74 days, P=.002) and cessation of ulcer/soft crust stage (3.61 days vs. 3.94 days, P<.001). The subjects were asked to reapply the medication following an exercise/shower; these applications were not accounted for, which is a flaw in the study.
8982417Habbema/199663 patients with RHL (98 episodes). RCT
Key resultsThis study was conducted in 2 centers, one in Netherlands and one in Belgium. 63 patients were accepted for the study, of which 22 also entered the cross over phase of the study, when they had a recurrence. 13 patients had a third episode of infection during the study period. A total of 98 episodes were evaluated (48 treated with 10% n-docosanol and 50 treated with an unknown placebo). Patients were randomly allocated and dispensed study medication. Treatment was self-initiated by the patient at the first sign or symptom of RHL. Of these, only 20 patients were given early treatment at the initiation of prodromal symptoms. The study assessed the effects of early and late application of n-docosanol/placebo on healing times. Early treatment with n-docosanol was found to show significantly shorter healing times (reduced healing time of 3.3 days, P=.05) when compared to late treatment with n-docosanol, and treatment with a placebo.
9134943Spruance /19971573 patients with RCL. RCT
Key resultsThis study was done in The United States across 31 different centers. Patients were randomly assigned and dispensed study medication. Treatment was self-initiated by the patient within 1 hour of first sign or symptom of a recurrence. Patients were instructed to apply the cream every 2 hours for a period of 4 days. Test group used 1% Penciclovir cream, and control group used a vehicle control cream. Penciclovir cream was found to decrease the duration of viral shedding, duration of pain, and accelerate lesion resolution as compared to placebo. The classic lesion healed 0.7 days faster in Penciclovir treated patients versus those treated with a placebo (median 4.8 days vs. 5.5 days, P< .001). There was improvement in pain and virus shedding in the test group.
11464183 Treister/2010Patients with Herpes Labialis.Review
Key results10% n-docosanol cream has similar efficacy as compared to other topical antiviral agents (5% acyclovir and 1% Penciclovir)
11559210McKeough/2001Guinea pigs infected with HSV-1. Experimental animal study
Key resultsUsing an animal model infected with HSV-1, the authors concluded that the efficacy of penciclovir cream was superior to acyclovir cream, which was superior to n-docosanol. The authors used two concentrations of n-docosanol: 10% and 12%, without a consistent control and both tests failed to have much effect in treating the experimentally induced HSV-1. The topical antivirals were used to treat a primary cutaneous herpes infection in guinea pigs and the results cannot be applied for treatment of RHL.
Evidence Search "Docosanol"[Mesh] AND "Penciclovir"[Mesh] AND "Herpes labialis"[Mesh]
Comments on
The Evidence
Apart from an experimental study, there are no studies comparing the efficacy of topical application of penciclovir versus 10% n-docosanol. Studies using the topical antivirals individually have shown promising results in treating RHL. Clinical trials are needed for a direct comparison between n-docosanol and Penciclovir to establish the efficacy of one over the other.
Applicability Recurrent Herpes Labialis occurs in 20-40% of the US population, causing severe discomfort and temporary disfigurement. The results obtained from these studies allow us to use 10% n-docosanol cream safely in the clinical setting for these patients. At present, n-docosanol is the only FDA approved over the counter antiviral, making it more accessible for patients to initiate early treatment for RHL.
Specialty (Oral Medicine/Pathology/Radiology) (General Dentistry)
Keywords Docosanol, Abreva, Penciclovir, Herpes Labialis, cold sore
ID# 2486
Date of submission 05/21/2013
E-mail meenachi.sellappan@ucdenver.edu
Author Meenachi Sellappan
Co-author(s) e-mail
Faculty mentor Pallavi Parashar, BDS, DDS
Faculty mentor e-mail pallavi.parashar@ucdenver.edu
Basic Science Rationale
(Mechanisms that may account for and/or explain the clinical question, i.e. is the answer to the clinical question consistent with basic biological, physical and/or behavioral science principles, laws and research?)
None available
Comments and Evidence-Based Updates on the CAT
None available