Kubiak, 52, was taken to a local hospital and admitted overnight. He underwent what the team described Monday as a "battery of tests." Kubiak will remain with medical personnel for at least the next 24 hours, the team announced.
"Our primary concern is, of course, with Gary's health and well-being," Texans general manager Rick Smith said in a statement. " ... Gary is alert, coherent and in good spirits. He is continuing to be evaluated and monitored."
Kubiak never lost consciousness and did not suffer a heart attack, NFL Media's Steve Wyche reported.
According to the team, Kubiak felt dizzy and light-headed, causing him to stop and kneel down as he made his way off the sideline for halftime.
Defensive coordinator Wade Phillips took over for Kubiak in the second half, and presumably he will continue to handle coaching duties while Kubiak recovers.
We wish coach Kubiak well and hope he has a speedy recovery.