Recurrent Herpes Labialis

Recurrent herpes labialis is repeated reactivation of latent herpes simplex virus, usually type 1, affecting the lips and perioral skin. Frequency is variable, with some people having one or two episodes yearly and others six or more.

• Reactivation is triggered by ultraviolet exposure, fever, menstruation, physical or emotional stress, dental procedures, trauma and immunosuppression.
• Frequent or severe recurrences should prompt assessment for HIV and other causes of reduced cellular immunity.

Stereotyped recurrences at the same site with a prodrome of tingling, then vesicles, ulceration and crusting over 7 to 10 days.

• Recurrences are milder than primary infection and without systemic symptoms in immunocompetent people.
• Prolonged, large, chronic ulcers occur in HIV and transplant recipients.
• Differential diagnosis: recurrent aphthous ulcer, angular cheilitis, contact dermatitis, fixed drug eruption, herpes zoster, recurrent impetigo, pemphigus, erythema multiforme, actinic cheilitis, squamous cell carcinoma.
• Complications: scarring and pigment change, bacterial superinfection, recurrent erythema multiforme, eczema herpeticum, herpetic keratitis with corneal scarring, psychological distress, transmission to partners and neonates.

Clinical, with PCR confirmation of atypical or chronic lesions.

• HIV test, glucose and full blood count in frequent or severe recurrences.
• Biopsy for non healing ulcers beyond 4 weeks to exclude malignancy or other causes.

Choose between episodic therapy started at the prodrome and daily suppression.

• Supportive: identify and avoid triggers, broad spectrum sunscreen lip balm SPF 30 or higher before sun exposure, cool compresses, analgesia, avoid contact while lesions are active.
• Pharmacological, episodic: valaciclovir 2 g twice daily for 1 day, or famciclovir 1500 mg once, or aciclovir 400 mg five times daily for 5 days, started at the first tingling. Suppression for six or more episodes yearly or severe disease: valaciclovir 500 mg once daily, or aciclovir 400 mg twice daily, or famciclovir 250 mg twice daily, for 6 to 12 months then pause to reassess. For sun triggered disease give valaciclovir 2 g twice daily for 1 day before planned heavy exposure. Immunosuppressed: aciclovir 400 mg three times daily for suppression.
• Procedures: none routinely; dental procedures may need prophylaxis in frequent triggers.
• Special groups: pregnancy, suppression with aciclovir 400 mg three times daily from 36 weeks if there is genital disease, and symptomatic episodes treated with aciclovir; children aged 2 years and over, aciclovir 200 mg five times daily for episodes; under 2 years, half this dose; renal impairment, reduce dose; HIV, antiretroviral therapy reduces frequency.
• Red flags: lesions not healing in 2 weeks, extensive spread, eye involvement, eczema herpeticum, resistance suspected in immunosuppression (give foscarnet 40 mg/kg IV every 8 hours under specialist care).
• Follow-up: review after 6 to 12 months of suppression; record frequency and consider stopping.