At the end of The Vampire Diaries Season 5, Episode 5 (“Monster’s Ball”) Silas drained Katherine, and Elena and Damon made a startling realization: Katherine was alive! But the sassy doppelganger’s brush with death won’t come without consequences.

“Once she's finally back to her sassy self again, it won't be long before she realizes that there's a major side effect — which will begin, or should we say fall out? — this week,” reports TVGuide.com. What could this “major side effect” be? Will she somehow be unable to stop bleeding?

We’re a little thrown off by the what could possibly “fall out” other than blood, unless, of course, Katherine’s allergies come back with a vengeance! According to the Episode 6 (“Handle With Care”) synopsis, “a desperate Katherine discovers a new and unexpected consequence of becoming human again.” This strange side effect will force her to go shack up with Caroline at Whitmore, who could probably use the company, seeing how her boyfriend just left her.

As for Katherine's blood and its effects on Silas, well, this former immortal is now human, but his dream of finally dying will “come with an unexpected hiccup,” reports TVGuide.com. Tessa strikes again!

What do you think the side effect could be? Hit the comments and let us know!

Catch the next episode of The Vampire Diaries on Thursday, November 7 at 8 p.m. ET on The CW.

Crystal Bell is an editor at Wetpaint Entertainment and our resident fangirl for all things The Vampire Diaries. Follow her on Twitter and Google+!