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.

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Narrowband UVB Minimal Erythema Dose (MED) Calculator

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Frequently Asked Questions

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

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

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

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

What is the dose adjustment for a missed phototherapy session?