Phototherapy

The Skin Center provides a new Narrow Band UVB full body therapy. Call 949-582-7699 to schedule a consultation.

UVB: Phototherapy

Initiating Narrow-band UVB for the Treatment of Psoriasis

Alice N. Do, D.O.a and John Y.M. Koo, M.D.b

 

Narrow-band UVB is effective for the treatment of psoriasis.3,8,10 The numerous protocols available in the literature may make it challenging for a practitioner, wishing to initiate narrow-band therapy, to choose the appropriate protocol. This article is a review of the literature on narrow-band UVB protocols and a guide to initiate therapy.

 

To commence therapy, a protocol that best suits the practitioner’s expertise level and the type of staff the practitioner has is chosen. The two main types of narrow-band protocols presented in this review are the Skin Type and MED (minimal erythema dose) protocols. MED and skin type testing to determine the dose of narrow-band UVB to begin treatment are detailed in a step-by-step process. Subsequent treatment doses are based on the skin’s response to the previous treatment.11 Further adjustments in light dose can accommodate missed treatments. Narrow-band light treatments are continued until psoriasis clears or almost clears, followed by tapering maintenance treatments. The goals of therapy are to establish and maintain control over psoriatic flares, and to balance the risks and benefits of narrow-band treatment.

 

Narrow-band ultraviolet B (NB-UVB) was introduced in 1976 and has been widely used for psoriasis, especially in Europe and Australia. It became available in the United States in 1996. NB-UVB emits a wavelength between 311-313 nm, which is most phototherapeutic for the clearance of psoriasis. NB-UVB has been shown to be more effective than broad-band ultraviolet B (BB-UVB)1,2,3 and almost as effective as PUVA for the treatment of psoriasis, but with a shorter remission time, and possibly with a lower risk of skin cancer.4,5,6 No standardized protocol has yet been established for NB-UVB for psoriasis.

This is a review of the literature on NB-UVB protocols and aims to help dermatologists feel more comfortable initiating NB-UVB and employing an optimal and simple-to-use treatment schedule. Table 1 illustrates the two kinds of NB-UVB protocols found in the medical literature.

In deciding which protocol to use, each protocol has its strengths and limitations. The skin type protocol is easier to practice, and can be executed by a smaller staff and takes less time than the MED protocol. It is suitable for a busy, high-volume practice. However, it requires a more experienced staff to determine skin type and be able to accurately predict the skin’s response to light. The MED protocol is more suitable for a less experienced staff because it specifically tests the skin’s response to light. MED skin testing still requires some knowledge of skin typing, to gauge the correct range of light doses to use in MED skin testing, as illustrated in Table 4. However, the MED protocol requires a significant investment of staff time to perform MED testing, which may or may not be feasible in a very busy practice or by a small staff. After choosing the protocol, determine the skin type (Table 3) and/or the MED (Table 4), as appropriate to the protocol. Then initiate therapy as illustrated in Table 2.

Begin at the initial dose indicated in Table 2. Assess the response during the next treatment visit. The next light dose is dictated by the skin’s response to the previous treatment, as illustrated in the “subsequent doses” row in Table 2.

Dose adjustment attempts to either maintain a barely perceptible erythema, which follows a more aggressive, erythmogenic strategy to therapy or, alternatively, it attempts to maintain just below a barely perceptible erythema, which follows a more con

From Wellington Regional Medical Centera and the Department of Dermatology,b University of California-San Francisco.

Conflict of interest: none.

 

Corresponding author: Alice Do, 2330 Wellington Green Drive, #302, Wellington, FL 33414 (561) 793-9644, (650) 438-1103 cellular, alice_do@hotmail.com, alice_do@adelphia.net

 

 

This article reprinted with permission from the Spring 2004 issue of Psoriasis Forum, the journal for National Psoriasis Foundation professional members.

 

For more information, visit www.psoriasis.org, call 800.723.9166 or contact the Psoriasis Foundation at:

6600 SW 92nd Ave., Suite 300

 

Portland, Oregon 97223

 

E-mail: getinfo@psoriasis.org

 

 

© National Psoriasis Foundation, Inc., Portland, OR 2004

 

2

 

 

 

 

 

 

 

 

 

 

 

 

 

 

PSORIASIS FORUM

 

SPRING 2004

 

Table 1: Description of the two types of NB-UVB protocols.

 

NB-UVB by Skin Type7,8

 

NB-UVB by MED7,8

Skin type is defined by the patient’s history of response to sunlight through burning and/or tanning.

This protocol requires that the treating practitioner be proficient in determining a patient’s skin type and predicting how the skin will respond to light treatment.

See Table 3: How to determine skin type.

This protocol does not require MED skin testing.MED (minimal erythema dose) is the minimal dose of NB-UVB light that causes a sharply-demarcated, uniform erythema, 24 hours after exposure, similar to a minimal/barely perceptible sunburn.

This protocol requires skin testing to determine the patient’s response to various doses of light, to determine the MED, and at which light dose to initiate therapy.

Knowledge of skin typing is also required to do MED skin testing. See Table 3.

To determine the MED, see Table 4: How to do MED skin testing.

 

 

3 SPRING 2004 PSORIASIS FORUM Skin Type NB-UVB Protocol

Adopted and modified from the Leone protocol.

MED NB-UVB Protocol

 

Adopted and modified from the Leone protocol.7

Initial Dose

Type I

Type II

Type III

Type IV

Type V

Type VI130 mJ/cm2

220 mJ/cm2

260 mJ/cm2

330 mJ/cm2

350 mJ/cm2

400 mJ/cm2

Start with 70% MED*

* Authors report starting with 70% MED,3,4,6,9,10,11,12 60% MED,2,7,8 or 50% MED.1,13,14 Hofer et al found that starting at 70% MED is more effective than 35% MED.15 The starting dose should be based on practitioner comfort and the patient’s history of response to light. For example, start closer to 70% if the patient has a history of tanning; start closer to 50% if the patient has a history of burning. Most centers start treatment with 70% MED.

 

 

Subsequent Doses

Skin response:

Severe erythema

Mild erythema

No erythema

15 mJ/cm2 for

25 mJ/cm2 for

40 mJ/cm2 for

45 mJ/cm2 for

60 mJ/cm2 for

65 mJ/cm2 forAdjustment:

No Tx. When burn resolves, 50% of last dose, then dose by <– 10%

same dose

dose by:

Type I

Type II

Type III

Type IV

Type V

Type VISkin response:

Severe erythema

Moderate

erythema

Barely

perceptible

erythema

No erythemaAdjustment:

No Tx. When burn resolves,

50% of last dose, then dose

by <– 10%

dose by 20%

same dose (erythmogenic

strategy) or slight dose to just

below the MED

(suberythmogenic strategy)

dose by 20%

Frequency of Tx9,13,16

 

3 times weekly**(Monday, Wednesday, Friday)

** Dawe et al have found no significant difference in clearing rates of psoriasis between five times weekly verses three times weekly to warrant the added inconvenience of more frequent treatments.9 Similarly, Leenutaphong et al found no significant difference in efficacy and clearing rates of psoriasis between two times weekly verses a four times weekly NB-UVB treatments.13 However, Cameron et al found that three times weekly NB-UVB cleared psoriasis significantly faster compared to two times weekly treatements.16 Most treatment centers have adopted a three times weekly (TIW) regimen. Subsequent treatments are not to be given less than 24 hours from the last treatment.

 

 

Adjustment for Tx

 

missed days:

1-7 days

8-11 days

12-14 days

15-20 days

21-27 days

28+ days

adjust dose:

dose per skin type

same dose

by 2 Tx’s worth

by 25%

by 50%

start over

 

 

 

 

The following guidelines are adopted and modified from Dermatol Nurs 1996;8(4):235-241 and serve only as a rough estimate of skin type.
Skin Type

Type I

Type II

Type III

Type IV

Type V

Type VIResponse to sun

Always burns, never tans.

Usually burns, sometimes tans.

Sometimes burns, usually tans.

Minimally burns, tans well.

Very rarely burns, tans profusely.

Almost never burns.Tone

Very fair skin. Blonde, red, or light brown hair. Blue, green, or gray eyes.

Fair skin. Blonde, red, or brown hair. Blue, green, gray, or brown eyes.

Black or brown hair. Brown eyes.

Light brown skin.

Moderately pigmented, brown skin.

Deeply pigmented.