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#94 Simplicity for simplex (cold sores): a pill in the pocket takes the tingling away

Do antivirals (oral or topical) or docosanol (Abreva®) improve healing time for patients with recurrent herpes labialis (cold sores)?

One or two doses of famciclovir may improve cold sore healing by about 2 days, while valacyclovir and longer courses of topical acyclovir or docosanol (Abreva®may improve healing by 0.5-1 day

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Placebo-controlled randomized controlled trials (RCT) of: 
  • Immunocompetent patients with recurrent cold sores (most ≥3 episodes/year). 
  • Starting treatment ≤1 hour of prodrome symptoms (unless specified). 
Oral antivirals: 
  • Three larger RCTs: 
    • Famciclovir: 1500mg x1 or 750mg BID x1 day (477 patients).1 
    • Valacyclovir: 1 day (2g BID) or 2 day (2g BID then 1g BID) (1856 patients).2 
    • Acyclovir: 400mg 5 times/day x5 days (174 patients).3 
  • Healing time improvement: 
    • Famciclovir: 2-2.5 days. 
    • Valacyclovir: 0.5~1 day. 
    • Acyclovir: not significant.  
Topical acyclovir: 
  • RCT: acyclovir 5% cream 5 times/day x4 days (1341 patients).4 
    • Healing time improved ~0.5 day.  
Docosanol 10% (Abreva®): 
  • RCT: docosanol 5 times/day started <12 hours of symptoms until healing occurred (743 patients).5 
    • Healing time improved ~0.75 day.  
  • No direct comparisons of different oral agents.1,2 
  • Many studies industry-supported1-4,5 and by same author.1-4 
  • Antivirals generally help cold sores heal in 4-5 days versus 5-6 days.1-4 
  • 35% of patients experience >4 recurrences per year.6  
  • Cost for treating one recurrence (using study dose regimens):  
    • Oral antivirals: ~$20 (valacyclovir 1 day) to $44 (acyclovir 5 days). 
    • Topical acyclovir (4g) ~$40 or docosanol (2g) ~$25. 
  • Health Canada has approved only valacyclovir for treating cold sores,7 while FDA has approved valacyclovir,8 famciclovir9 and acyclovir9,11 (oral and topical).  
updated jan 29, 2018

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  • Hoan LInh Banh BScPharm PharmD
  • Michael R Kolber MD CCFP MSc
  • Tony Nickonchuk BScPharm CDE APA

1. Spruance SL, Bodsworth N, Resnick H, et al. Single-dose, patient-initiated famciclovir: A randomized, double-blind, placebo-controlled trial for episodic treatment of herpes labialis. J Am Acad Dermatology. 2006; 55:47-53.

2. Spruance SL, Jones TM, Blatte MM, et al. High-dose, short duration, early valacyclovir therapy for episodic treatment of cold sores: results of two randomized, placebo-controlled, multicenter studies. Antimicrob Agents Chemother. 2003; 47:1072-80.

3. Spruance SL, Stewart JC, Rowe NH, et al. Treatment of recurrent herpes simplex labialis with oral acyclovir. J Infect Dis. 1990; 161:185-90.

4. Spruance SL, net R, Marbury T, et al. Acyclovir cream for treatment of herpes simplex labialis: results of two randomized, double-blind, vehicle-controlled, multicenter clinical trials. Antimicrob Agents Chemother. 2002; 46:2238-43.

5. Sacks SL, Thisted RA, Jones TM, et al. Clinical efficacy of topical docosanol 10% cream for herpes simplex labialis: a multicenter, randomized, placebo-controlled trial. J Am AcadDermatol. 2001; 45:222-30.

6. Dreno B, Malkin JE, Saiag P, et al. Patients’ profile, burden of disease and quality of life in recurrent herpes labialis: a survey conducted in USA and France. Journal of the European Academy of Dermatology and Venereology. 2012; 26:1454-60.

7. Valtrex [drug product monograph].Mississauga, ON. GlaxoSmithKline Inc, 2009.

8. FDA Drug efficacy supplemental approval in 2002. Accessed June 7, 2013.

9. FDA Drug efficacy supplemental approval in 2006. Accessed June 7, 2013.

10. Zovirax (capsules, tablets, suspension) [package insert]. Research Triangle Park, NC. GlaxoSmithKline, 2007.

11. Zovirax (5% cream) [package insert]. Research Triangle Park, NC. GlaxoSmithKline, 2011.

Authors do not have any conflicts of interest to declare.