Seems like a lot of back-room drama for “How I Met Your Mother”. The producers are working hard to save the high quality/low ratings comedy. It appears that news of Britney’s cameo didn’t sit well with a recently announced guest star. Ausiello has the scoop:

Britney Spears’ havoc-wreaking cameo on How I Met Your Mother has already claimed its first victim. A Mother insider confirms that Alicia Silverstone — who was slated to appear in a multi-episode arc as Ted’s dermatologist/lover — has dropped out and will be replaced by Scrubs’ Sarah Chalke.
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Pink is the New Blog reports that Silverstone bowed out because she didn’t want to be overshadowed by Spears, who, per my sources, will play an assistant to the dermatologist now being portrayed by Chalke.

Ausiello goes on to confirm that they are attempting to create another role for Silverstone.

I don’t blame her. Her appearance would be competing with Spears for the wrong reasons. I know that producers are trying to get buzz about the show, but is Britney Spears the type of buzz you want?

That being said, Sarah Chalke is a great sitcom actress, so adding her to a show is never wrong. I’m eager to see if what other drama is ahead for this bubble-show.