Why apply alcohol after completing 2 weeks of of Fluorouracil?

I am currently midway through 2 weeks of using Fluorouracil on my face to address precancerous cells. It's not been too bad yet but I understand the worst is yet to come.
As I've researched this, I have become a little confused. My dermatologist said that after I finish the 2 weeks, I should apply alcohol to my face for the following week. I have to imagine that putting alcohol onto what is essentially raw skin, perhaps even broken skin, will be extremely painful.
In contrast, most of what I have read from others is that they apply moisturizers such as Aquaphor or even vaseline to soothe the skin. Has anyone else been advised to use alcohol? I'm wondering what the medical reason might be for applying alcohol and if there is a medical benefit, what might be a less painful way to achieve that benefit.