Polymorphic light eruption is a fairly common skin rash triggered by exposure to sunlight or artificial ultraviolet light. It lasts for up to 2 weeks, healing without scarring.
Polymorphous Light Eruption - Mayo Clinic
Mum is so allergic to sunshine she blisters really badly, UK News
Polymorphic light eruption & juvenile spring eruption
Polymorphic light eruption - Altmeyers Encyclopedia - Department Dermatology
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Polymorphous light eruption: Pictures and treatments
Sun Allergy, Solar Urticaria
Polymorphous light eruption - Wikipedia
Sun Sensitivity (Photosensitivity) and Eczema