What MED-based starting NB-UVB dose is recommended?

If MED tested: start at 50-70% of MED; if Fitzpatrick-based: Type I: 70 mJ/cm²; Type II: 100 mJ/cm²; Type III: 130 mJ/cm²; Type IV: 160 mJ/cm²; Type V: 200 mJ/cm²; increase by 10-20% each session 3x/week.

What response rate is expected for NB-UVB in psoriasis?

NB-UVB achieves PASI 75 in ~65-70% of patients after 20-30 sessions; remission typically lasts 4-6 months; maintenance 1x/week reduces relapse; most effective for plaque psoriasis; less effective for pustular or erythrodermic.

How many NB-UVB sessions are needed for vitiligo repigmentation?

Vitiligo: 24-36 sessions for initial assessment; face/neck responds best (>75% repigmentation in responders); hands/feet respond poorly; PUVA or excimer laser for resistant sites; continue for minimum 6 months before declaring failure.

What cumulative lifetime NB-UVB dose is associated with skin cancer risk?

Cumulative lifetime dose >1000-1500 J/cm² NB-UVB associated with increased NMSC risk; annual skin cancer surveillance recommended for high cumulative dose patients; much lower NMSC risk compared to PUVA (psoralens + UVA) historically.

What is the dose adjustment for a missed phototherapy session?

If missed 1 session: no change; missed 1 week: reduce dose 25%; missed 2 weeks: reduce 50%; missed 3+ weeks: restart from beginning; burns from over-dosing: skip 1 session and reduce next by 25-50% until erythema resolves.

Narrowband UVB Minimal Erythema Dose (MED) Calculator

Calculates starting narrowband UVB dose based on Fitzpatrick skin type and MED testing, dose escalation schedule for psoriasis and vitiligo phototherapy, and cumulative lifetime UVB dose monitoring.

⚕ Clinical Disclaimer: These calculators are for educational and reference purposes only. Always verify results with qualified clinical judgment and current clinical guidelines. Do not use as a sole basis for medical decisions.

How It Works

Calculates starting narrowband UVB dose based on Fitzpatrick skin type and MED testing, dose escalation schedule for psoriasis and vitiligo phototherapy, and cumulative lifetime UVB dose monitoring

Each component has a specific meaning:

Fitzpatrick skin type — The fitzpatrick skin type recorded for the scenario being assessed.
MED testing — The med testing recorded for the scenario being assessed.
Dose escalation schedule — The dose escalation schedule recorded for the scenario being assessed.

Note: Interpret the nb-uvb med result against the thresholds and context described above.

How to Use

Enter the Fitzpatrick skin type, MED testing, dose escalation schedule for the scenario you are assessing. Calculates starting narrowband UVB dose based on Fitzpatrick skin type and MED testing, dose escalation schedule for psoriasis and vitiligo phototherapy, and cumulative lifetime UVB dose monitoring. Use the nb-uvb med result to inform your calculation.

Related Calculators

Fitzpatrick Phototype

Medical Calculators

PASI Score