Cold sores (herpes labialis)
Recurrent HSV-1 (sometimes HSV-2) infection with vesicular lesions on the vermilion border of the lips. Triggers: stress, fever, sun exposure, menstruation. AAD 2022 and the Spanish AEDV 2023 consensus support topical aciclovir or penciclovir during prodrome in episodic disease; oral aciclovir, valacyclovir, or famciclovir for 1–3 days in frequent or severe recurrences. In patients with more than 6 episodes per year, suppressive therapy is discussed.
ICD-10 B00.16 drugs
Also known as: Cold sores, Fever blisters
Drugs used for this condition
- AValacyclovirFirst line · Antiviral – aciclovir prodrugUsed in recurrent herpes labialis as short courses. Dose 2000 mg twice daily for 1 day (total 4 g). Spruance 2003 showed this 1-day regimen shortens the episode by 1 day versus placebo. An alternative to longer aciclovir regimens.
- BAciclovirFirst line · Antiviral – nucleoside analogueUsed in recurrent herpes labialis. Topical 5% cream is applied 5 times daily for 4 days, starting in prodrome. The Cochrane 2007 meta-analysis showed topical aciclovir reduces episode duration by 0.5–1 day with minimal toxicity. Oral aciclovir 400 mg three times daily for 5 days is more effective in severe recurrences. In patients with more than 6 episodes per year, suppressive therapy 400 mg twice daily long-term is used.
- BFamciclovirSecond line · Antiviral nucleoside analogue for herpes infections (HSV-1, HSV-2, VZV)For recurrent herpes labialis, famciclovir is used as a single-day 1500 mg oral regimen. The Spruance 2006 RCT showed the episode shortens by about 1 day on average (NNT about 10), provided the dose is taken in the prodromal phase (tingling, burning before vesicles appear). If lesions are already established, efficacy is much lower. AEDV positions famciclovir as an alternative to valaciclovir; first line for moderate episodes is topical 1% penciclovir cream.
- CL-lysineAdd-on therapy · Essential amino acidMany patients take L-lysine to reduce recurrent labial herpes episodes. A 2017 systematic review by Mailoo and Venkatakrishnan pooled about 12 studies, 7 of them RCTs: doses of 1–3 g/day reduced episode frequency or severity, but the meta-analysis was weak because of heterogeneous protocols and short follow-up. Herpes guidelines do not include lysine as standard. The standard for severe frequent recurrence remains antiviral aciclovir or valaciclovir. The review advises caution in patients with cardiovascular disease and gallstones (theoretical risk via reduced arginine). With rare mild episodes, many dermatologists accept a trial of lysine alongside discussing the plan with the doctor.
- CPropolis (bee product)Add-on therapy · Bee product, supplement. Not registered as monomedicine in EU or AEMPS; OTC segment in Italy and GermanyTopical propolis in balms and creams is used for herpes labialis. The Vynograd 2000 RCT (Phytomedicine) compared topical Canadian propolis with topical aciclovir and placebo in HSV-2 genital herpes: propolis showed statistically significant healing acceleration. For herpes labialis (HSV-1) topical propolis balms may be considered in mild flare-ups. First-line for frequent labial herpes recurrences remains oral aciclovir, valaciclovir or famciclovir (CDC 2021). If propolis was recommended for severe recurrent herpes instead of systemic antiviral therapy, consider seeking a second opinion.
Marketing claims without evidence base
The drug is promoted for these uses outside international guidelines. Each entry below is analyzed against AEMPS, FDA, EMA, Cochrane and major RCTs.
How to read tiers A–F
Evidence tiers belong to the drug-indication pair, not to the drug as a whole: the same substance can be A for one condition and F for another.
- AStrong evidence – first or second line in international guidelines
- BRecommended in selected cases
- CStudy data contradict each other
- DBenefit not proven, no documented harm
- FDocumented harm, or risk without benefit