Polymorphous Light Eruption Treatment & Management

Updated: May 22, 2018
  • Author: Noah S Scheinfeld, JD, MD, FAAD; Chief Editor: Dirk M Elston, MD  more...
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Medical Care

UVA1 therapy can harden the skin against the development of polymorphous light eruption (PMLE). A case of PMLE that failed UVA1 therapy has been reported; a woman aged 37 years developed an recalcitrant PML that lasted 5 weeks after completion of UVA1 phototherapy. [41]

Prophylactic therapy (eg, avoiding sunlight, wearing protective clothing, using sunscreen) remains a key factor in the care of patients with PMLE. Sunscreens with high sun protection factor (SPF) values are not protective against UV-A–induced PMLE. Systemic vitamin C and vitamin E do not prevent photoprovocation test reactions in persons with PMLE.

In a randomized, double-blinded, placebo-controlled clinical study by Hadshiew et al, the efficacy of a new topical formulation was compared with a broad-spectrum sunscreen. [42] The new product contained 0.25% alpha-glucosylrutin (a natural, modified flavonoid) and 1% tocopheryl acetate (vitamin E). Thirty patients with a history of PMLE were pretreated with the formulations 30 minutes prior to daily photoprovocation with UV-A irradiation of 60-100 J/cm2 to the upper arms.

The authors found a statistically significant difference (P< .001) between the antioxidant-containing formulations and placebo and between the sunscreen-only formulation. Only a single patient treated with the new antioxidant UV-protective gel formulation developed clinical signs of PMLE in the area treated. In comparison, 62.1% of the placebo-treated areas and 41.3% of the sunscreen-only treated areas showed mild-to-moderate signs of PMLE. The authors suggested that combining a potent antioxidant with a broad-spectrum sunscreen is far more effective in preventing PMLE than sunscreen alone. Also see Sunscreens and Photoprotection.

Gruber-Wackernagle et al evaluated the preventive effect of a cream containing calcipotriol (an analog of calcitriol, 1,25-dihydroxyvitamin D3) in a randomized double-blinded placebo-controlled intraindividual half-body trial. [43] Thirteen patients with PMLE applied cream (calcipotriol or placebo) topically to symmetrically located pairs of test areas twice daily for 7 days before photoprovocation with solar-simulated UV radiation was begun.

The authors used a specific PMLE test score based on affected area, skin infiltration, and pruritus to rate symptom severity at 48, 72, and 144 h after the first photoprovocation exposure. They found pretreatment with calcipotriol, compared with placebo, significantly reduced PMLE symptoms on average by 32% (P=0.0022) over the time series, suggesting a possible benefit from prophylactic use of topical 1,25-dihydroxyvitamin D3 analogs in patients with PMLE. [43] However, this does not change the standard of care for PMLE.

Jeanmougin et al studied the effectiveness 0.25% alpha-glucosyl-rutin, 1% vitamin E, and a broad-spectrum highly UVA–protective sunscreen (SPF 15; persistent pigmentation darkening 6) under real solar exposure conditions in the spring and summer. [44] The cream was applied every 2 hours after the first summer exposure. No topical or systemic treatments to prevent PMLE were used; dermatologists checked patients after the summer was over and interviewed them.

In this study, 52 of 54 patients finished study, and 67% of patients had no eruptions, 19% had minor eruptions, and 13% had severe eruptions of PMLE. [44] Pruritus, which had been present in all patients the year preceding the study, was not observed in 69% of patients and was unbearable for only 3 patients (compared with 27 patients before the study preparation was used).The dermatologic assessment was that global efficacy was approximately 80%, with inadequate results in 10% of cases; specifically, it was deemed excellent for 35 patients and good for 7 patients.

DeLeo et al reported that sunscreen with 4 UVA filters (ie, ecamsule 3%, octocrylene 10%, avobenzone 2%, and titanium dioxide 5%) was more effective for preventing PMLE flares than a sunscreen with a triad of UVA blockers. [45] Other studies support the use of UVA blockers to help prevent PMLE, [46] including a report that describes a lower percentage of PMLE (0% at 2 mg/m2; 33% at 1 mg/m2) in subjects who used high UVA sunscreen protection versus those who used lower UVA sunscreen protection (73% at 2 mg/m2; 80% at 1 mg/m2). [47]

Prophylactic phototherapy or photochemotherapy at the beginning of spring for several weeks may prevent flare-ups throughout the summer. PUVA was found to be superior to UV-B in several studies, controlling the outbreaks in 90% of patients. [48] Oral prednisone may be useful in conjunction with phototherapy to avoid eruption during therapy. Narrow-band UV-B (311 nm) may be an acceptable alternative to PUVA. In a study of 25 patients with severe PMLE, both modalities were equally effective. [49] Barolet and Boucher report on the use of light-emitting diode (LED) nonthermal therapy as a prophylactic measure for PMLE. [50]

When preventive measures fail and light therapy is ineffective or contraindicated, pharmacologic treatment assumes its role. Topical corticosteroids are useful, as would be expected in many dermatoses associated with lymphocytic skin infiltrate. Tachyphylaxis and skin atrophy limit their use. Antihistamines may help with pruritus. Systemic steroids may be needed to suppress acute flares or extensive generalized eruption. Adverse effects of prolonged systemic steroid use include decreased glucose tolerance, osteoporosis, impaired immunity, and weight gain. Obviously, this treatment can only be offered intermittently and for a short period of time. It may also be considered for patients going on vacation or for those patients experiencing other unavoidable sun exposure.

Antimalarials at low doses are sometimes helpful, especially in patients with a large papular variety of PMLE. Beta-carotene, which is effective in erythropoietic protoporphyria, may be an alternative to chloroquine. [51] Oral carotenoid preparation (beta-carotene and canthaxanthin in a daily total dose of 100 mg) was compared to hydroxychloroquine (200 mg qd). Both offered full sun tolerance in an equal but small, percentage of patients, when compared to a placebo.

Some authorities believe that vitamin therapy is helpful in the treatment of PMLE. Nicotinamide was successful in 60% of 42 patients treated with 3 g/d orally for 2 weeks. [52] The rationale for its use was the knowledge that it blocks the formation of kynurenic acid, a photosensitizer that may play a role in PMLE. Ahmed et al found that oral vitamin E supplementation (400 IU) and use of sunblock decreased the markers of oxidative stress and lipid peroxidation in patients with PMLE. [53]

Azathioprine was reported to be effective in 2 cases of recalcitrant severe disease at 0.8-2.5 mg/kg/d for 3 months. [54] In one patient, the effect lasted up to 4 months after the discontinuation of therapy. However, the limited available data and azathioprine toxicity should necessitate extreme caution in choosing this form of treatment.

Interest in the use of thalidomide for a number of dermatoses (eg, Behçet syndrome, cutaneous lupus, porphyria cutanea tarda [PCT], PMLE) is reemerging. The immunomodulatory action on subsets of T cells was proposed. Thalidomide (50-200 mg PO qhs) has reportedly been very effective for Native American patients with PMLE. The most commonly described adverse effects with thalidomide are sedation, constipation, and weight gain.

The most serious complications of thalidomide are peripheral neuropathy and teratogenicity. Unfortunately, no recent published controlled trials of this drug being used in the treatment of PMLE are available. Thalidomide is available only to pharmacies and physicians participating in the System for Thalidomide Education and Prescribing Safety (STEPS) program. A new variant of thalidomide is available.

Lenalidomide (Revlimid, formerly known as Revimid) is the first of a new class of oral cancer drugs called IMiDs. This immunomodulatory drug is chemically similar to thalidomide. However, it is more powerful in the laboratory. It appears to lack some of the more common adverse effects of thalidomide. Its role in the treatment of PMLE is uncertain.



Avoiding sunlight during the hours of most intense UV irradiation (from 10 am to 2 pm) and wearing protective clothing (eg, hats, gloves, long sleeves) should be emphasized to polymorphous light eruption (PMLE) patients. Blue denim clothing is particularly beneficial in terms of sun protection. Wide range sunblocks with a high SPF should be applied and reapplied during the day. Polypodium leucotomos extract may be of some benefit. [55]