From the Research
Acute lichenoid pityriasis should be treated with narrow-band UVB phototherapy as the first-line treatment, given its high efficacy and relatively low risk of side effects, as supported by the most recent and highest quality study 1. The condition is characterized by recurrent crops of small, red-brown papules that develop into vesicles and eventually form crusted lesions.
- Treatment options include:
- Topical corticosteroids, such as triamcinolone 0.1% or betamethasone 0.05%, applied twice daily to affected areas for 2-4 weeks
- Oral antibiotics like erythromycin (500mg four times daily) or tetracycline (500mg twice daily) for 2-4 weeks, due to their anti-inflammatory properties
- Phototherapy, particularly narrowband UVB, administered 2-3 times weekly for 6-8 weeks, for resistant cases
- Systemic immunosuppressants like methotrexate (starting at 7.5-15mg weekly) for severe presentations The exact cause of acute lichenoid pityriasis remains unknown, but it is believed to be an immune-mediated reaction possibly triggered by viral infections, medications, or other environmental factors, as discussed in 2 and 3.
- Patients should be monitored regularly, as the condition can rarely progress to more severe forms or ulceronecrotic variants, with a mortality rate of up to 25% in the most severe cases, as noted in 2. Given the lack of high-level evidence studies on PL treatment, as highlighted in 1 and 4, the choice of treatment should be based on the most recent and highest quality studies available, with a focus on minimizing morbidity, mortality, and improving quality of life.