From the Guidelines
Phototherapy for psoriasis typically lasts around 20-25 treatments for broadband UVB (BB-UVB) and 15-20 treatments for narrowband UVB (NB-UVB), with sessions given 3-5 times a week. The treatment duration can vary depending on the severity of psoriasis, skin type, and individual response to treatment 1.
Key Considerations
- The initial improvement often occurs within 4 weeks of therapy for BB-UVB, while response is observed at 8-10 treatments for NB-UVB 1.
- Maintenance therapy may prolong remission, with sessions spaced further apart (once weekly, then biweekly, then monthly) 1.
- NB-UVB is generally more effective and requires fewer sessions than BB-UVB, with a remission rate of 38% after 1 year compared to 5% for BB-UVB 1.
Treatment Details
- The dosage of UVB may be administered according to the Fitzpatrick skin type or the minimal erythema dose (MED), with subsequent dosages adjusted accordingly 1.
- Patients should protect unaffected skin during treatment and use moisturizers afterward to manage dryness, a common side effect.
- The most recent and highest quality study suggests that NB-UVB is a safe and effective treatment option for psoriasis, with no significant association found with basal cell carcinoma, squamous cell carcinoma (SCC), or melanoma 1.
From the Research
Typical Length of Phototherapy for Psoriasis
- The typical length of phototherapy for psoriasis can vary depending on the specific treatment protocol and the individual patient's response to treatment 2.
- For narrowband UVB (NB-UVB) phototherapy, typical regimens involve dosing 3 times per week for at least 3 months 2.
- In a study comparing the efficacy of methotrexate/NB-UVB phototherapy combination vs. NB-UVB phototherapy, the mean number of weeks required to achieve 75% reduction in Psoriasis Area and Severity Index (PASI) Score was significantly less in the combination group (mean 6.5 weeks) compared to the NB-UVB monotherapy group (mean 12.1 weeks) 3.
- Another study found that the mean number of weeks required for achieving clearance (90% reduction in PASI Score) was 6.11 ± 1.28 weeks in the combination group (NB-UVB plus methotrexate), 11.42 ± 2.36 weeks in the NB-UVB alone group, and 20.87 ± 4.21 weeks in the methotrexate alone group 4.
- The duration of phototherapy can also depend on the severity of the psoriasis, with more severe cases requiring longer treatment periods 5, 6.
- It is essential to note that treatment must be independently developed to suit each participant's needs, and the length of phototherapy can vary significantly from one patient to another 2.