The England international, on loan from Liverpool, had been out of action for several weeks with a hamstring problem that he sustained on his debut for the Hammers.
However, the 23-year-old returned during yesterday's 2-1 win over Queens Park Rangers at Loftus Road.
"I have been dying to get back. I was devastated when I got injured, but I've worked hard and I've been in the gym every day," he told the club's official website.
"As soon as I stopped feeling the hamstring a week or two ago, I wanted to get back on the pitch, but they wouldn't let me because they told me it wasn't right. I've had to keep working on it and I've got it right. I'm absolutely fine."
Reports have claimed that Carroll may now be included in the England squad for upcoming World Cup qualifiers later this month.