Why Is Effexor Effective In Improving Facial Skin Condition?

Hello, I have pale skin tired and sunken eyes and generally kinda look awful haha but I noticed that my skin improved heavily last year when I was on anxiety medication effexor, though once i stopped taking the medication my skin slowly went back to crummy. I drink 8 cups of water a day, eat healthy and sleep healthy, also take milk thistle and fish oil vitamins and still I see no results, how come effexor helped with my skin condition?