Season 9, Episode 7: "The Slicer"

Boy, that looks like an allergic reaction.

Have you been wearing a fake beard?

-No. -Well, what have you been doing?

Nothing. I got up, I ran some errands...

...went to Sara and apologized--

Whoa, back up. Dr. Sitarides? Yeah, what happened there?

Well, I tried to apologize. It didn't go over too well.

There's your hives.