Wide receiver Beckham walked off the pitch and into the locker room before the final play of the first half of the 34-13 defeat.
It came after Beckham courted controversy when he made remarks over the Giants and in particular quarterback Eli Manning.
“Uhh, I don’t know,” Beckham had said when asked if the Giants have a quarterback problem. “I feel like … He’s not going to get out of the pocket.
“We know Eli’s not going to run it. Can he still throw it? Yeah. It’s cool catching it shallow and trying to take it, but I want to go over the top of somebody.
“I want to be the best that I can. I don’t feel like I’m given the opportunity to be the very best that I can be.”
Beckham left the pitch having had two catches on four targets for 12 yards in the first half during NFL Thursday Night Football.
He had left early against New Orleans Saints two weeks ago to get an IV.
And the 25-year-old has revealed it was the same thing against Philadelphia.
“I was cramping so I was trying to go and get an IV,” Beckham said.
“The half time break is really only 5, 10 minutes.
“So if I can use a couple of extra seconds to get an IV and come back out, that’s really all it was.”
Beckham has reportedly been reprimanded for the previous comments by the Giants.
According to Jay Glazer of Fox Sports, Beckham was fined an undisclosed amount by the team.
It’s not clear exactly which comments Beckham has been fined for with the receiver previously insisting he is not in the wrong for his comments.
“I don’t regret anything, I don’t regret anything that I said. If it took that for us to come together as a team like we did today, I can take that every single time,” Beckham said earlier this week.
“I spoke to the team just to kind of relay the message that sometimes stuff comes off the wrong way. Words can be portrayed in any kind of light. The conversation is between us.”