Photodermatitis

...However, in reality, ICD and ACD may coexist, or ICD may begin first and then ACD may occur, making it difficult to clearly distinguish between the two even when referring to the rash type and subjective symptoms. When a substance undergoes a chemical reaction when exposed to ultraviolet light and the product causes ICD or ACD, the clinical form of photodermatitis is photodermatitis, in which dermatitis occurs only in areas exposed to sunlight. Topical steroids are generally used to treat dermatitis, and are often effective, but when it is difficult to treat, it is necessary to identify the causative substance through patch tests, usage tests, and elimination tests, and remove it from the environment. ...

*Some of the terminology that mentions "photodermatitis" is listed below.

Source | Heibonsha World Encyclopedia 2nd Edition | Information

…しかし現実にはICDとACDが共存したり，最初ICDで始まり，次にACDが起こるなど，発疹型や自覚症状を参考にしても，両者をはっきりと識別しえない場合もある。物質に紫外線があたって化学変化が起こり，その生成物がICDやACDを起こすときは，臨床的には日光のあたった部位にのみ皮膚炎が起こる日光皮膚炎photodermatitisの形となる。　皮膚炎の治療には一般にステロイド外用剤がよく用いられ，有効なことが多いが，難治のときにはパッチテストや使用試験，除去試験で原因物質をみつけ，環境から除くことが必要である。…

※「photodermatitis」について言及している用語解説の一部を掲載しています。

出典｜株式会社平凡社世界大百科事典 第２版について | 情報