Sun Allergy

You step into the sun — and your skin revolts. Red patches, itching welts, burning heat, small blisters spreading across your arms and décolleté. Sometimes twenty minutes is enough, sometimes a single clear spring day. Your body responds to what nourishes all living things with resistance. The sun that bestows warmth, enables photosynthesis, lifts the mood — becomes an attack on your skin.

Medicine speaks of polymorphic light eruption, photoallergic reaction, or Mallorca acne — of a hypersensitivity of the skin to UV radiation. Precise terms that describe the phenomenon but leave one question open: why does your system consider light, of all things, a threat? Why does your largest sensory organ — the one that is touched and that touches — respond with alarm to something as elemental as the sun?