What are the reasons why the penis is difficult to erect?

Patient's question:

Just the past two months

Doctor's answer:

Hello, since I had a girlfriend, I realized that my penis cannot get erect easily, especially after drinking some alcohol. It's due to kidney deficiency. You are currently experiencing kidney deficiency. I suggest taking Liuwei Dihuang Wan, Jin Gu Jing Wan, and Hui Ren Shen Bao orally, which can usually cure it within about three months. I also suggest that you avoid drinking alcohol and eat less spicy, greasy, and stimulating food.