My dog started to suddenly leap up for no apparent reason

[kenucklehead]

My dog, an Australian Shepherd, is 4y8m. About a month ago, she started to exhibit an odd behaviour. While lying down, for no apparent reason, she leaps up and freaks out. I notice this because I have hard wood floors and the nails of her hind paws suddenly make scratching noises. She does this so suddenly, her hind paws don't get any traction and it's like she's running on the spot, slipping and scratching up my floors!

I've had these floors for 3 years and she has never done anything like this until the past month. It's disconcerting because I don't know what's causing it and because she's scratching the hell out of my relatively new floors. She does this several times a day.

On a possibly related note, she has epilepsy and has been on Phenobarbital for the past 2.5 years. She's been seizure free for the past year and a half. I haven't notice any other odd behaviour and when I catch her doing this, she appears alert and aware.

Anyone have any thoughts on this?

[Ghilly]

Have you checked her very well for fleas?  After she jumps up does she bite or scratch at herself at all?

I have seen a few dogs do this over the years, they will react with a jump to a flea bite but if it's a flea they will usually pay attention to the area of the bite after they jump up.  

If not fleas, could there be some other type of insect in your house that's biting her?  

Ghilly