This document updates the scientific evidence and clinical practice regarding narrowband UVB phototherapy (NB-UVB) in dermatology. The review addresses indications, therapeutic regimens, safety aspects, combinations with systemic and biologic agents, and adaptation to special populations. NB-UVB remains a first-line therapy for psoriasis, vitiligo, atopic dermatitis, early mycosis fungoides, and photodermatoses due to its efficacy, safety, and cost-effectiveness. Emerging evidence supports its integration with next-generation systemic therapies. This update provides recommendations for its application in the era of targeted therapies, with an emphasis on efficiency and patient-centered care.
The use of ultraviolet radiation (UVR) as phototherapy evolved from the classical proposals of Goeckerman and the use of psoralens with ultraviolet A radiation (PUVA) to reach a major milestone with the introduction of narrowband UVB (NB-UVB) therapy. These advances, together with the implementation of other modalities such as excimer laser, UVA-1 therapy, and photodynamic therapy (PDT), have considerably expanded its spectrum of clinical applications. In 2005, the Spanish Photobiology Working Group (GEF) published a consensus document that compiled both the main aspects of scientific evidence and routine clinical practice regarding UVR phototherapy.1 This document became a reference for dermatologists and phototherapy centers, as well as a useful resource for support and negotiation with healthcare managers and administrators. Years later, an update focused on psoriasis was published.2 Twenty years after its publication, the GEF proposes an update on the most relevant developments that have occurred over these years, incorporating an international perspective with the support of the Phototherapy Working Group of the Ibero-Latin American College of Dermatology (Colegio Ibero-Latinoamericano de Dermatología, CILAD).
During recent decades, progress in phototherapy has been mainly technical, with innovations in equipment and delivery systems rather than conceptual or therapeutic foundations. Overall, NB-UVB phototherapy maintains its validity in most indications in which it is considered a good alternative, in its different modalities (whole-body cabins, localized units, or excimer laser), due to the multiple pathophysiological mechanisms on which it exerts effects (Supplementary Table 1).3,4 In contrast, PUVA therapy has generally experienced a decline in routine use, although it remains a first- or second-line indication in some conditions, whereas UVA-1 therapy has undergone limited development but is particularly useful in some diseases with a deep component, such as scleroderma or certain variants of cutaneous lupus.5,6
In parallel, the advent of targeted therapies for inflammatory dermatoses has substantially modified the therapeutic approach. Defining the current role of phototherapy in this new context, including its indications, advantages, and possible combinations, constitutes one of the main objectives of this update.
With an approach oriented toward daily clinical practice, this new document maintains its primary objective of optimizing the use of NB-UVB phototherapy, consolidating its relevance as a safe, effective, and cost-effective therapeutic tool in a constantly evolving medical environment. The guidelines presented here are intended as recommendations designed to support clinical decision-making in the management of multiple dermatoses. Therapeutic choice should be individualized according to patient characteristics and available technical resources (Supplementary Table 2).
Materials and methodsThis manuscript was developed by a group of phototherapy experts belonging to the GEF of the Spanish Academy of Dermatology and Venereology (AEDV). For its development, previous guidelines and consensus documents from the group, as well as the scientific literature available in the Medline and Cochrane databases, were reviewed. In addition, the clinical experience accumulated by GEF members was incorporated. The manuscript was subsequently evaluated by all members of the GEF and by members of the CILAD Phototherapy Working Group, who performed a structured search in PubMed and LILACS to ensure updated bibliographic coverage and provide an international perspective. The contents were revised in those areas that generated the greatest discussion or required updating.
This document represents an abridged version requested by the editors with the aim of presenting a concise and easily accessible document. The full version of the document, including all tables, can be found in the Supplementary material.
General conceptsNB-UVB therapy is based on the emission of UVR within a limited spectral range centered at 311nm. Although this spectrum was initially identified in experimental studies as the most effective and optimal for the treatment of psoriasis, its use has become consolidated as the preferred option for most dermatoses treated with phototherapy in dermatology departments.7,8
One of its main advantages lies in the fact that the emission spectrum excludes wavelengths <300nm, which are associated with a greater risk of adverse effects, especially erythema, without providing relevant therapeutic benefits (Fig. 1).
Unlike broadband UVB (BB-UVB) lamps, which are currently obsolete, NB-UVB sources optimize both therapeutic efficacy and safety by minimizing unnecessary radiation exposure. This combination of efficacy and safety has established NB-UVB as a first-line treatment in the phototherapy of psoriasis, vitiligo, atopic dermatitis (AD), and plaque parapsoriasis/mycosis fungoides, among other inflammatory skin diseases.9
Indications for NB-UVB phototherapyPsoriasisNB-UVB is considered a first-line therapy in patients with moderate or extensive plaque psoriasis who do not respond adequately to topical treatments, as well as in pregnant patients or women during breastfeeding. Moreover, it is particularly useful in patients with contraindications to systemic treatments or who prefer to avoid the risks associated with biologic agents, including children and immunosuppressed patients.9–12
In patients who achieve prolonged remission periods after NB-UVB therapy, this modality constitutes an appropriate alternative, whereas in those with early relapses it is reasonable to consider a change in therapeutic strategy.13
Suberythemogenic regimens are generally more appropriate in clinical practice, as they are associated with better tolerance and promote adherence to treatment.11,14
Individualization of dosing during clinical follow-up is essential, allowing treatment adjustment according to patient response and tolerance, thereby minimizing the risk of adverse effects.10,11
Clinical response assessment may begin from the second week of treatment onward, taking into consideration that maximum benefit is usually achieved between the 6th and 8th weeks (20–24 sessions).10–12,15
Compared with PUVA therapy, NB-UVB presents a more favorable safety profile, making it the preferred option in most patients, although remission periods may be somewhat shorter.16,17
In patients with more extensive psoriasis or with thicker infiltrated lesions, therapeutic alternatives other than NB-UVB phototherapy should be considered, taking into consideration that in current clinical practice biologic therapy tends to be the preferred option in more severe cases.14,18
NB-UVB phototherapy in psoriasis and targeted therapyThe advent of targeted therapies in psoriasis and their positioning as first-line therapies require a redefinition of the role of NB-UVB phototherapy within the therapeutic armamentarium.18,19
Phototherapy may be used in combination with biologic agents or small molecules with the aim of enhancing clinical response or accelerating lesion clearance. Although long-term safety data for these combinations remain limited, preliminary results suggest a favorable profile in terms of efficacy and tolerability.18,20
Table 1 illustrates the available evidence on the combination of NB-UVB phototherapy with targeted therapies.
Main results of combined NB-UVB and targeted therapy.20
| Combination | Key results | Adverse effects | Important notes |
|---|---|---|---|
| NB-UVB+etanercept | - All patients who failed to achieve PASI 75 with monotherapy achieved PASI 75 with combination therapy.- 43% achieved PASI 90 compared with 21% with etanercept alone. | - Not specified. | - Significant histological improvement in treated plaques.- Requires adherence (>80%). |
| NB-UVB+adalimumab | - PASI 75: 95%; PASI 90: 75%; complete clearance: 55% at 12 weeks.- PASI 75 retention: 65% at 24 weeks. | - Mild-to-moderate UV erythema. | - Better outcomes in irradiated body halves. |
| NB-UVB+ustekinumab | - PASI reduction of 82% in irradiated halves versus 54% in non-treated halves. | - Not specified. | - Localized benefit. |
| NB-UVB+apremilast | - PASI 75: 73% after 12 weeks.- Additional improvements in pain, pruritus, and quality of life (77%, 69%, and 70%, respectively). | - Mild-to-moderate erythema in 38%. | - Improvements in quality-of-life indices and symptoms. |
NB-UVB phototherapy is an alternative in patients with moderate flares of AD or in those requiring maintenance treatment after achieving a favorable clinical response with other therapeutic modalities.21
Available evidence positions NB-UVB phototherapy as a reference therapeutic option, especially in patients with insufficient response to topical treatment or contraindications to systemic therapies.21–23
NB-UVB phototherapy in AD and targeted therapyAs in psoriasis, the advent of targeted therapy raises questions regarding the role of phototherapy in AD in the era of targeted therapies.23–25
NB-UVB phototherapy may be considered an appropriate strategy as an initial therapeutic option in patients with AD showing insufficient response to topical treatment, especially before initiating immunosuppressive or immunomodulatory treatments, and particularly in cases of moderate AD.24,26
The use of NB-UVB phototherapy within the first few weeks of dupilumab treatment in patients with severe AD may be associated with more rapid clinical improvement of lesions and symptoms, especially during the first month of treatment vs dupilumab monotherapy.27
Since the clinical response to NB-UVB phototherapy may take a few weeks, it may be appropriate to consider the use of a short course of oral corticosteroids before or concomitantly, while simultaneously maintaining treatment with emollients and topical corticosteroids.25,26
NB-UVB phototherapy may be used as supportive treatment in combination with other systemic therapies, both during the initial weeks to accelerate clinical response and in situations of disease exacerbation.28
VitiligoNB-UVB phototherapy is one of the most effective therapeutic options for inducing repigmentation in patients with vitiligo, a disease in which therapeutic alternatives remain limited.29–31
NB-UVB phototherapy is indicated in patients with insufficient response to topical treatment and/or with extensive or progressive involvement. Since treatment usually requires a prolonged period, it is essential to discuss with the patient the balance between benefits and expected duration, as well as realistic expectations regarding response.32,33
In terms of safety and efficacy, NB-UVB presents advantages over other therapeutic modalities, such as BB-UVB, topical corticosteroids, or topical PUVA, which supports its preferential use in clinical practice.33,34
Response rates are higher in patients with darker phototypes and in those with shorter disease duration.35
The early appearance of repigmentation signs, usually between 6 and 12 weeks after treatment initiation, allows early identification of responder patients, facilitating individualized management and continuation of therapy only in those with favorable response.35
Response to NB-UVB phototherapy varies according to anatomical location, with better results observed on the face, intermediate responses on the trunk, and more limited repigmentation on the extremities, thus justifying consideration of combined or alternative strategies in less reactive areas.36,37
Of note, the benefits obtained with NB-UVB may diminish over time, highlighting the need to inform patients about the possible loss of repigmentation after treatment discontinuation.38,39
Although NB-UVB phototherapy generally presents a favorable safety profile, the limited information regarding cumulative doses in pediatric patients with phototypes I–III advises extreme caution and prolonged follow-up in this patient population.40
NB-UVB phototherapy in vitiligo and targeted therapyThe combination of NB-UVB therapy with JAK inhibitors may represent an alternative in patients who do not respond to one of the two treatments or with the objective of enhancing therapeutic response. However, there are limited data regarding the long-term safety of this combination.41–44
Plaque parapsoriasis and cutaneous T-cell lymphomaNB-UVB therapy remains a first-line therapy in the management of plaque parapsoriasis and mycosis fungoides.45–47
NB-UVB therapy may be offered as first-line therapy in patients with various forms of plaque parapsoriasis and early-stage mycosis fungoides. Even when, as is common in these patients, diagnostic uncertainty exists, the safety profile of the treatment and its broad applicability favor its empirical use.48–51
In cases of disease progression or treatment failure, PUVA therapy and other systemic options should be considered to optimize clinical control.49,52
PhotodermatosesNB-UVB phototherapy is an effective therapeutic tool in the management of various photodermatoses, highlighting its usefulness in the induction of UVR tolerance (“hardening”). This effect is especially relevant in conditions such as polymorphous light eruption (PMLE) and solar urticaria and, to a lesser extent, in hydroa vacciniforme and chronic actinic dermatitis.53,54
In patients with PMLE, NB-UVB has demonstrated success rates comparable to PUVA therapy, with the advantage of a superior safety profile since it does not require the use of psoralens. A short regimen of 3 sessions per week for 1 month may be effective in many patients, preventing exacerbations during the summer.55,56
Once the treatment regimen has been completed, patients should be advised to perform brief sun exposures to maintain desensitization, which may be combined with the use of antioxidants and photoprotective agents.57
NB-UVB phototherapy has proven to be well tolerated and effective in preventing relapses of solar urticaria.53,58,59
Experience is limited in other photodermatoses such as chronic actinic dermatitis and actinic prurigo, and no recommended regimens currently exist, although caution in dose escalation and an individualized treatment schedule are recommended.60
Other indicationsNB-UVB therapy has been successfully used in a variable number of inflammatory dermatoses that are difficult to treat with other therapeutic alternatives. However, in all these cases, the absence of a clear indication and the uncertainty regarding expectations of success should be emphasized and communicated to the patient (Table 2).3
Other indications for NB-UVB therapy.
| Clinical category | Diseases or conditions |
|---|---|
| Inflammatory dermatoses | - Atopic dermatitis23- Seborrheic dermatitis60- Psoriasis11 |
| Autoimmune dermatoses | - Vitiligo30- Lichen planus131- Pityriasis rubra pilaris132 |
| Photodermatoses | - Drug-induced photosensitivity53,77- Hydroa vacciniforme53,77- Nodular prurigo133- Actinic prurigo53,77- Polymorphic eruption of pregnancy53,77 |
| Pruritus-associated dermatoses | - Aquagenic pruritus134,135- Pruritus associated with polycythemia vera134,135- Uremic pruritus134,135 |
| Neoplastic or precancerous dermatoses | - Lymphomatoid papulosis136- Pityriasis lichenoides chronica137- Mycosis fungoides49 |
| Deposition diseases or rare disorders | - Erythropoietic porphyria138- Perforating dermatoses139 |
| Diseases associated with immunologic alterations | - Granuloma annulare140- Graft-versus-host disease141 |
| Rare dermatologic conditions | - Pityriasis rosea of Gibert142- Eosinophilic folliculitis143- Alopecia mucinosa |
| Others | - Chronic urticaria137 |
Before prescribing and initiating NB-UVB phototherapy for any dermatosis, it is essential to perform a comprehensive patient evaluation to determine clinical suitability and general conditions for receiving this therapeutic modality (Table 3). Similarly, circumstances requiring caution in phototherapy centers before and during treatment should be considered (Supplementary Table 3).
Aspects that should be evaluated before initiating NB-UVB phototherapy.
| Aspect that should be evaluated | Key points |
|---|---|
| Indication and suitability of treatment | - Confirm indication for NB-UVB.- Evaluate available therapeutic alternatives.- Inform the patient about: treatment characteristics, pros and cons, expectations of success, and recommendations. |
| Past medical history | - Skin phototype.- History of malignant or premalignant skin lesions.- Risk factors for cutaneous neoplasms.- Current immunosuppressive treatments.- Previous history of phototherapy and obtained results.- History of the dermatosis under treatment.- Current medications with emphasis on phototoxic or photoallergic agents. |
| Clinical examination | - Determine the extent and severity of the dermatosis (use standardized indices such as PASI or EASI when applicable).- Rule out the presence of malignant or premalignant skin lesions. |
| Determination of phototype (or MED) | Assess skin phototype or determine the MED to adequately adjust the protocol. |
| Contraindications | - Identify severe DNA repair disorders (e.g., xeroderma pigmentosum, Bloom syndrome).- Evaluate high risk of aggressive cutaneous neoplasms (e.g., familial dysplastic nevus syndrome).- Confirm that UVR will not worsen the underlying disease (e.g., lupus erythematosus). |
| Precautions and exceptions | - Consult the table of conditions where NB-UVB use is limited, ensuring a balanced risk/benefit assessment.- Use with caution and under strict monitoring in specific cases. |
| Laboratory tests and monitoring | - No prior laboratory testing is required unless a treatment-exacerbated disease is suspected (e.g., lupus erythematosus).- Routine laboratory monitoring is not required.- May be used during pregnancy. |
| Explanation and information provided to the patient | - Provide a detailed information sheet. |
| Informed consent | - Obtain informed consent detailing side effects and expectations.- Explain pros and cons, benefits, and treatment risks. |
MED: minimal erythema dose; PASI: Psoriasis Area and Severity Index; EASI: Eczema Area and Severity Index.
Reference according to phototype is the most practical approach in NB-UVB therapy because it allows faster treatment initiation with response expectations and remission times similar to protocols based on minimal erythema dose (MED).50
In NB-UVB phototherapy protocols based on phototype, dose increments per session may generally range between 10 and 20% and up to 40%, depending on the regimen used.61–63
More conservative increments, in the range of 5–10% per session, may achieve efficacy comparable to higher increments, such as 20%, with better patient tolerability.50
Close clinical follow-up within the first 6–8 sessions is key to optimizing treatment, allowing individualized adjustment of the regimen according to cutaneous tolerance.64
In patients with good initial tolerance, the use of larger dose increments may be considered, whereas in those with lower tolerance, maintaining a more conservative and cautious approach is more appropriate.64,65
Several proposed therapeutic protocols are shown in Table 4.
Therapeutic protocols for NB-UVB phototherapy.
| Authors | Initial dose | Increments per session | Maximum dose |
|---|---|---|---|
| Picot et al. | 100mJ/cm2 phototype II140mJ/cm2 phototype III200mJ/cm2 phototype IV | 15–40% | 1,500mJ/cm2 |
| Zanolli et al. | 300mJ/cm2 phototypes I and II500mJ/cm2 phototypes III and IV800mJ/cm2 phototypes V and VI | 100mJ/cm2 phototypes I–IV150mJ/cm2 phototypes V and VI | Not specified |
| Halasz | 180–240mJ/cm2 phototype II240–280mJ/cm2 phototype III280–320mJ/cm2 phototype IV280–400mJ/cm2 phototypes V and VI | 30–40mJ/cm2 phototype II60–70mJ/cm2 phototype III90–100mJ/cm2 phototype IV120–130mJ/cm2 phototype V150–160mJ/cm2 phototype VI | 1,400mJ/cm2 (mean dose) |
| Carrascosa | 200mJ/cm2 phototype II250mJ/cm2 phototype III300mJ/cm2 phototype IV400mJ/cm2 phototype V | 10% phototype II10–20% phototype III20% phototype IV | 1,200–1,500mJ/cm2 phototype II1,500–1,700mJ/cm2 phototype III1,800–2,300mJ/cm2 phototype IV3,000mJ/cm2 phototype V |
| Har Simrat Kaur | Psoriasis:phototype I–II: 100mJ/cm2phototype III–IV: 200mJ/cm2phototype V–VI: 300mJ/cm2 | Linear increments of 50–100mJ/cm2 per session for all phototypes.Percentage increments: 20% for psoriasis. | Psoriasis:phototype I–II: 2,000mJ/cm2phototype III–IV: 3,000mJ/cm2phototype V–VI: 4,000mJ/cm2Average therapeutic dose ≈50% of the maximum recommended dose. |
In hyperkeratotic and pustular palmoplantar psoriasis lesions, due to the thickness of the stratum corneum in these anatomical sites, it is suggested to start with higher doses (from 300mJ) and reach maximum doses of up to 3,000mJ. In the absence of contraindications, combination with acitretin or methotrexate is advisable.76
NB-UVB phototherapy protocols based on MED represent a valid alternative to phototype-based regimens, initiating treatment with doses corresponding to 50–70% of the MED.48
Dose increments per session usually range between 10 and 20%, and may reach up to 40%, depending on the regimen used and patient tolerance.66
This type of protocol may allow a faster clinical response, with possible reduction in total treatment duration and cumulative dose, without relevant differences in overall efficacy vs other regimens.67
Session frequencyThe frequency considered optimal for psoriasis treatment is 3 sessions per week. Administration of 2 weekly sessions may result in a slower response, although similar by the end of treatment. Administration of 4–5 sessions per week may accelerate lesion clearance, although it also increases the risk of adverse effects.68
Maximum dose per sessionMaximum doses per session vary considerably depending on patients and protocols used. It is advisable to adopt as the maximum dose the one that allows satisfactory clinical evolution of the dermatosis.64,69
Management of missed sessionsIn daily practice, this is a common situation that may condition decreased efficacy and a higher incidence rate of adverse effects.64,70 Various actions in cases of missed sessions are proposed in Table 5.
Approach to missed NB-UVB phototherapy sessions.
| Situation* | Recommended regimen |
|---|---|
| Missing 1 session | Maintain the previous dose. |
| Missing 1 week of treatment | Reduce the dose by 25%. |
| Missing 2 weeks of treatment | Reduce the dose by 50%. |
| Missing >2 weeks | Restart treatment. |
Maintenance regimens should be reserved for patients whose dermatosis presents greater morbidity or a history of rapid recurrences after previous phototherapy cycles. In these cases, gradual reduction in session frequency is recommended, performing 2 weekly sessions for 2–4 weeks, followed by 1 weekly session for a similar period.64,69,71
In exceptional situations, prolonged maintenance therapy with 1 weekly or monthly session may be considered, always weighing the risk of long-term adverse effects.11,72,73
In the current therapeutic context, where effective alternatives exist for most classical NB-UVB indications, the possibility of choosing other therapeutic strategies should be considered in patients presenting repeated recurrences after discontinuation of phototherapy.18
Protocols according to dermatosisIn other dermatoses, protocols established for psoriasis are usually adopted. However, specific considerations may be made in certain conditions where substantial cumulative experience already exists.
VitiligoIn vitiligo treatment, it is recommended to start with a dose of 200mJ/cm2, progressively increasing it through percentage increments according to the suberythemogenic protocol used in psoriasis, or alternatively with fixed increases of 50mJ/cm2 per session.32,34
The optimal dose should be that which produces mild, asymptomatic erythema while avoiding adverse reactions. In most cases, doses between 600 and 1000mJ/cm2 per session are sufficient, although each patient should be evaluated individually.32,34
It is advisable to reconsider treatment continuation in slow responders if, after 30–50 sessions, no evident clinical improvement is observed.74
Atopic dermatitisIn AD, due to the greater predisposition to erythema, a more gradual dose increase vs psoriasis is recommended. For example, it may be useful to repeat each dose twice before performing a new increase.23,75
Maximum doses per session are usually lower than those used in other conditions and are determined individually according to clinical response and pruritus control, avoiding the appearance of erythema. In general, these doses remain below 1000mJ/cm2 per session.75,76
Polymorphous light eruptionTreatment regimens for PMLE are similar to those used in vitiligo. It is recommended to start with a dose of 200mJ/cm2, increasing it at each session by approximately 10% or through fixed increases of 50mJ/cm2, until reaching a maximum dose per session of 500–700mJ/cm2.77,78
Possible exacerbation of the dermatosis within the first few sessions should be carefully monitored, adjusting the dose according to the patient's individual tolerance.79
Adverse effects of NB-UVB therapyShort-term adverse effectsErythemaAlthough some degree of erythema is a common finding, it becomes significant and bothersome for the patient in a minority of cases and is exceptionally the cause of definitive treatment discontinuation. This adverse effect is more frequent in obese patients and elderly individuals.79,80
Erythema may be recorded semiquantitatively as E0 (no erythema), E1 (barely perceptible, asymptomatic), E2 (well defined, with mild discomfort), E3 (well defined, painful), and E4 (painful erythema with blisters). E3 and E4 sunburn-type reactions occur infrequently.70,71,80
Strategies to prevent and manage erythema are shown in Table 6.
Prevention strategies and protocol modification in response to NB-UVB erythema.
| Prevention strategies for NB-UVB-associated erythema | |
|---|---|
| Strategy | Description |
| Recording and substitution of medications | Replacement of drugs with phototoxic potential. |
| Suberythemogenic regimens | Allow good results with more sessions vs erythemogenic regimens. |
| Avoid sun exposure | Avoid sun exposure on the day of the session; prudent exposure on weekends. |
| Individuals >70 years | Greater caution with dose increments due to increased erythema risk. |
| Protocol modification in response to erythema development | |
|---|---|
| Condition | Recommended action |
| Mild asymptomatic or slightly bothersome erythema | Maintain the previous dose. |
| Moderate erythema with symptoms (pain, pruritus) | Suspend 1–2 sessions and reassess before restarting treatment. |
The appropriateness of prophylactic acyclovir use may be individually assessed in patients with a past medical history of recurrent herpes virus infections.81
PruritusPruritus is a common adverse effect during the first phototherapy sessions, generally associated with mild erythema. In most cases, it responds favorably to the use of emollients or oral antihistamines with sedative effects.64,70
Since it usually occurs concomitantly with erythema, preventive and management measures are the same as those described in the corresponding section for this adverse effect.
Asymptomatic blistersThe very rare development of blisters in treated areas has been described, which usually resolve spontaneously within 96–120h.82
Guttate hypomelanosisLesions consistent with guttate hypomelanosis have been described during NB-UVB treatment and may resolve after treatment discontinuation.83
Ocular adverse effectsNB-UVB may be associated with ocular adverse effects, mainly keratitis or conjunctivitis, which justifies the systematic use of protective goggles during all treatment sessions.84
Since the amount of UVB radiation penetrating through the eyelids is minimal, phototherapy may be safely performed with closed eyes in patients with eyelid involvement, provided that appropriate safety measures are followed.85
This practice requires detailed patient information and active patient involvement in strict adherence to therapeutic staff instructions to guarantee procedural safety.
Potential long-term adverse effectsPhotoagingIt is recommended to limit phototherapy cycles to 2 per year and consider alternative therapeutic strategies when prolonged maintenance regimens are required.86
CarcinogenesisEvidence from systematic reviews and observational studies does not demonstrate a significant association between NB-UVB phototherapy and an increased risk of nonmelanoma skin cancer or melanoma, even in patients exposed to a high number of sessions.87–92
Administration of a very high number of NB-UVB sessions, including >500 sessions, has not been associated with an increased risk of skin cancer vs patients not treated with phototherapy.30
Of note, after a high number of sessions (≥200), an increased incidence rate of actinic keratoses has been described, thus justifying appropriate clinical follow-up in these patients.87
The overall risk of carcinogenic effects appears to be especially low in patients with skin phototypes III and IV, a factor that may be considered in the individual assessment of the benefit-risk balance.93
Prevention of adverse effectsMultiple strategies that help prevent the occurrence of adverse events associated with NB-UVB phototherapy are described in Supplementary Table 4.
NB-UVB therapy in special situationsUse of phototherapy during pregnancy and breastfeedingNB-UVB phototherapy constitutes a safe therapeutic alternative during pregnancy, with no contraindications described in this context.94
During pregnancy and in women of childbearing age wishing to conceive, supplementation with folic acid at a dose of 0.8mg/day may be considered, taking into consideration the possible reduction in folic acid levels due to photodegradation during prolonged treatments, although this issue remains controversial.95–97
During this period, the increased risk of melasma development should be considered, making it appropriate to emphasize facial photoprotection, except in areas requiring specific phototherapy treatment.98
Furthermore, NB-UVB phototherapy may be used during breastfeeding, since no alterations in breast milk quality or production, nor adverse effects in the infant, have been observed.99,100
Safety of phototherapy in childhoodNB-UVB phototherapy constitutes a safe therapeutic option and, in many cases, preferable to other alternatives during childhood, provided that standard safety measures are respected.101,102
There is no established age limit for the use of phototherapy, and the child's ability to comply with minimum safety measures and tolerate session duration should be assessed individually.103,104
Given the possible long-term cumulative effect of UVR and the described association between childhood sunburns and melanoma, it is especially important to minimize episodes of erythema during NB-UVB treatment in this age group.105,106
Available data suggest a favorable medium-term safety profile in pediatric patients with higher skin phototypes (IV–VI), which may be considered in individual treatment assessment.107
Vaccination and NB-UVB therapyThere is no evidence that NB-UVB therapy interferes with the response to immunization; therefore, vaccination may be carried out according to general recommendations based on the patient's age and clinical profile.108
ComorbiditiesNB-UVB phototherapy is the first-line therapy for the management of dermatoses responsive to this modality in patients with relevant comorbidities, such as chronic liver disease, renal insufficiency, or cardiovascular disease, regardless of their nature or severity.109–111
NB-UVB phototherapy has demonstrated efficacy and good tolerability in patients with chronic HIV infection, especially in those with stable virological control or on effective antiretroviral therapy. Its use in this context has not been associated with deterioration of immune function or with an increased incidence of opportunistic infections or cutaneous neoplasms.112,113
In patients with HIV infection and extensive psoriasis not controllable with topical treatments, NB-UVB phototherapy may be considered a preferred therapeutic option within the overall management of the disease.114
Therapeutic combinationsThe application of mineral oil or 5% oleic acid before NB-UVB therapy increases the efficacy profile of this radiation source in psoriasis. In contrast, thick-layer petrolatum or oily excipients containing salicylic acid are counterproductive because they act as sunscreens and should be avoided before treatment sessions.115,116
The use of topical corticosteroids is appropriate as an adjunct to phototherapy in psoriasis in areas poorly accessible to ultraviolet radiation, such as skin folds or the scalp.117
The combination of vitamin D derivatives and/or calcineurin inhibitors and/or topical retinoids with narrowband UVB may enhance repigmentation in vitiligo.118–123
The combination of acitretin and NB-UVB is effective in moderate or extensive plaque psoriasis with insufficient response to phototherapy or retinoid monotherapy.124–126
The combination of methotrexate and NB-UVB is safe and demonstrates clear therapeutic synergism in dermatoses responsive to both treatments.127–130
Table 7 illustrates different therapeutic combinations, indications, and reported benefits in NB-UVB phototherapy.
Therapeutic combinations described with NB-UVB phototherapy.
| Therapeutic combination | Main indications | Benefits |
|---|---|---|
| NB-UVB+retinoids | Psoriasis, cutaneous T-cell lymphoma | Increased therapeutic efficacy and reduction of retinoid dose. |
| NB-UVB+methotrexate | Moderate-to-severe psoriasis atopic dermatitis morphea | Faster clinical improvement, reduction of monotherapy side effects. |
| NB-UVB+cyclosporine | Severe psoriasis graft-versus-host disease | Reduction in the required cyclosporine dose in short or transitional regimens (during therapeutic rotation) and improved symptom control. |
| NB-UVB+biologics (e.g., anti-TNF-α) | Psoriasis with partial therapeutic response to biological therapy (therapeutic optimization) | Therapeutic synergism, therapeutic optimization, improved tolerability, greater immunologic control. |
| NB-UVB+topical and systemic JAK inhibitors | Vitiligo atopic dermatitis | Promising effects on repigmentation and inflammation reduction. |
| NB-UVB+topical therapies (e.g., corticosteroids, calcipotriol) | Psoriasis, atopic dermatitis, vitiligo Lichen planus, morphea | Rapid localized improvement, complementary effect in combination. |
| NB-UVB+PUVA | Erythrodermic and pustular psoriasis, cutaneous T-cell lymphoma (CTCL) | Therapeutic complement when NB-UVB alone is insufficient. Therapeutic synergism. |
NB-UVB phototherapy is a relevant and fully current therapeutic option for the management of multiple inflammatory dermatoses and photodermatoses, even in the current era of targeted therapies.
Its favorable safety and efficacy profile and cost-effectiveness, along with extensive cumulative experience, supports its consideration as a first-line therapy or as part of combined therapeutic strategies in well-established indications such as psoriasis, vitiligo, atopic dermatitis, early forms of cutaneous T-cell lymphoma, and various photodermatoses. In these settings, the emergence of new targeted therapies is leading to a repositioning of therapeutic indications in each of these diseases and further opening new possibilities for combination therapy.
Appropriate patient selection, protocol individualization, close follow-up, and rational integration with other therapeutic modalities are key to optimizing outcomes.
This document aims to provide an updated and practical framework to facilitate clinical decision-making, promoting efficient, safe, and patient-centered use of NB-UVB phototherapy in current dermatological practice within a broad and international clinical setting.
FundingNone declared.
Conflicts of interestJosé-Manuel Carrascosa has served as consultant/speaker/investigator for Janssen Pharmaceuticals Inc, Pfizer, Almirall SA, Lilly, AbbVie, Sanofi, Novartis, Celgene, Amgen, Leo Pharma, UCB, Pfizer-Wyeth, Sandoz, and BMS.
Javier Ubogui is Medical Director and shareholder of Psoriahue and shareholder and consultant for LUMED.
Isabel Belinchón has served as consultant/speaker/investigator for Janssen Pharmaceuticals Inc, Pfizer, Almirall SA, Lilly, AbbVie, Novartis, Celgene, Biogen, Amgen, Leo Pharma, UCB, Pfizer-Wyeth, Sandoz, BMS, and MSD.
José Sebastián Fagre has served as speaker for AbbVie, Lilly, Adium, Janssen, L’Oréal, and Novartis and is Medical Director of PIEL FAGRE – Psoriahue.
Pablo Fonda-Pascual has served as consultant/speaker/investigator for Janssen Pharmaceuticals Inc, Pfizer, Almirall SA, Lilly, AbbVie, Sanofi, Novartis, Leo Pharma, AstraZeneca, Galderma, UCB, and Incyte.
Francisco José Navarro Triviño has served as consultant/speaker/investigator for Galderma, Pfizer, Almirall, Lilly, AbbVie, Sanofi, Novartis, and Leo Pharma.
María Fernanda Ordóñez-Rubiano has served as consultant/speaker for Sanofi, AbbVie, Eli Lilly, Galderma, BioPas, and Pfizer and has received research funding (grants paid to institutions) from Sanofi, AbbVie, and L’Oréal.
Cristian Pizarro-Vargas has served as principal investigator in clinical studies for Merck, Sanofi, and AstraZeneca.
Tatiana Riveros Recine has served as consultant for Galderma and Janssen and as speaker for Sanofi.
Jose Luis López-Estebaranz has served as consultant/speaker/investigator for Almirall, BMS, Babe, Janssen JJ, Leo-Pharma, Lilly, AbbVie, Bioderma, Galderma, UCB, Novartis, Invasix, Isdin, and Incyte.
The remaining authors declare no conflicts of interest related to the present consensus document.
Uncited referencesThe following are the supplementary data to this article:
