Am i dumb or what? I still don’t understand why is he taking medications??#－.－)

You can reread it was in the early chapter of the new season

I think he was suffering from insomnia as he said he couldn't sleep. honestly this isn't the first time he has said this. I also think he was depressed.

Health issues

I thought it was some form of psychiatric medication to manage depression which was contributing to his insomnia

Pretty sure its a mixture of various things which correlate to worsening his health including stress, depression, insomnia, a lack of apatite, his diet etc.