Hi Lisa, These are tape worms and they are caused by her swallowing a flea that is carrying the tape worm egg. You can safely wait until Tues. to get some medication for her. She actually will pass them on her own with no medication- the med simply speeds the process up. However- she WILL continue to get them as long as there is a flea around so your best control is flea control. Try the once a month products like Advantage or FrontLine. I like to rotate them as fleas are terrible this year.
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