Speaking to Digital Spy at the Monte Carlo Television Festival, Gordon explained that the effect of Carrie's work on her personal health will be what the writers "play on at the very beginning of the year".
Gordon also promised that Brody's political career will be a big part of the show, saying that it will be "developed very early on".
Watch Howard Gordon speaking to Digital Spy about Homeland below:
Gordon added that he believes the relationship between Carrie and Brody is "basically a tragic love story", promising that it "hasn't gone away" in the new season.
He also teased that the video Brody made in the season finale will "figure into" the new episodes, explaining that the clip was "unexpurgated opportunity [for Brody] to explain what's going on inside his mind".
"I think he presents himself not as some crazy guy, but actually as somebody who had thought a lot about it," he said.
Elsewhere, Gordon described Saul as Carrie's "conscience" in many ways, praising star Mandy Patinkin by saying: "[He] did just such a phenomenal job of taking that character places we never imagined he could go."
Homeland will return with new episodes later this year on Showtime in the US and Channel 4 in the UK.