From the Research
Aciclovir is recommended for pityriasis rosea at a dose of 800 mg five times daily for 7 days, as it has been shown to reduce the duration and severity of symptoms, particularly when started early, as supported by the most recent and highest quality study 1.
Key Points
- Pityriasis rosea is a self-limiting viral exanthem that typically resolves on its own within 6-8 weeks.
- Aciclovir may help reduce the duration and severity of symptoms in certain cases, particularly when started early.
- The recommended dose of aciclovir is 800 mg five times daily for 7 days, with a dose of 20 mg/kg (maximum 800 mg) four times daily for 7 days for children.
- Symptomatic treatment with antihistamines, topical steroids, or moisturizers is usually sufficient for most patients.
- The theoretical basis for using aciclovir is that pityriasis rosea may be associated with human herpesvirus 6 or 7 reactivation in some cases, though this connection remains controversial.
Evidence
- A network meta-analysis published in 2024 found that acyclovir was the best option for patients with pityriasis rosea that have extensive, persistent lesions or systemic symptoms, with a SUCRA score of 0.92 1.
- Another study published in 2018 found that acyclovir was superior to placebo for complete regression of lesions at week 1, with a Risk Ratio of 5.72 (CI95% 2.36-13.88) 2.
- A randomized controlled trial published in 2011 found that a low dose of acyclovir (400 mg five times a day for 1 week) was effective in reducing erythema and shortening the duration of pityriasis rosea 3.
Considerations
- Patients should be informed that even with treatment, the rash may take several weeks to completely resolve, and that aciclovir treatment represents an off-label use for this condition.
- The use of aciclovir should be considered on a case-by-case basis, taking into account the severity of symptoms and the potential benefits and risks of treatment.