NBC News says former "NBC Nightly News" anchor Tom Brokaw felt light-headed Thursday morning and was taken from the set of MSNBC's "Morning Joe" to an area hospital for evaluation. The show is being broadcast from Charlotte this week. 

Brokaw, now an NBC news special correspondent, said in a tweet Thursday morning that he "mistakenly took half a dose of Ambien and made less sense than usual."

The full statement from NBC News: "On the set of 'Morning Joe' this morning, Tom Brokaw felt light-headed. Out of an abundance of caution, he was taken to a hospital. He is being evaluated and is in good spirits."

And Brokaw's tweet: