The effect of the painkiller usually lasts twenty-four hours. I took one pill this morning before I went out. Why does it become ineffective so soon? Could it be that the painkiller is useless for me?

About twenty minutes later, the painkiller finally took effect. The severe pain was gradually relieved and later turned into a dull pain that she could endure.

Looking at Estelle worriedly, Rebecca said, “Estelle, what’s wrong with you? This medicine... Its name is so long. What is it for?”

Estelle shook her head with a smile and said, “I just had a sudden stomach ache.”

“Stomach ache?”

“Yes.”

“It’s troublesome to have stomach problems. My...