潰瘍

胃に潰瘍が出来る。

An ulcer forms in the stomach.

薬(くすり)を飲み始めると、すぐに痛みなどの症状はとれてきますが、すぐに潰瘍がなおるわけではありません。

When you start taking medicine it begins working on symptoms, like pain, right away, but that doesn't mean that the ulcer heals right away.