If something goes to someone's head, it makes that person think that they are very important and makes them a less pleasant person.

Don't let fame/success go to your head. 别让名声／成功冲昏你的头脑。

If alcohol goes to your head, it makes you feel slightly drunk.

Champagne always goes straight to my head. 香槟总是把我弄得头昏脑胀。