Credit: Steven Lawton/FilmMagic

Stay out of Kourtney Kardashian's way if she hasn't eaten.

"I'm such a bitch when I'm hungry, like stone cold biatch," she Twittered Monday night.

Kourtney, 31 -- mother to nearly 8-month-old son Mason -- likely hasn't had time to enjoy a nice meal, as she's been running around promoting the new season of E!'s Keeping Up With the Kardashians, debuting Aug. 22.

On Friday, she sat on a panel alongside her sibs to chat about the show. Two days later, she hit the Teen Choice Awards red carpet -- and fell slightly ill.

"I have a major [sore] throat so off to bed," she Twittered after the show.

By Monday, she was back on her feet: "I love Mondays," she wrote. "They are all about getting things done. Major productive day."