you could do it a couple times a day, it looks very dry and brittle already and she probably will lose it, if it does not improve in a couple days time, i think it will just dry up further and fall off. I had a little one just tonight loose about 3/8th an inch of his tail that had been bitten by a sibling, the same thing happens really, the area just dries up and will fall off, took about a week for it to happen, just keep it clean with some betadine and thats about all you can do. I also had a similar situation with one of my older dragons, he lost about 1/4 inch of his tail due to a little bit of shed that was stuck, he has a very dark end to his tail so it went un noticed even though im very careful when my dragons shed to be sure they shed completely, somehow it was missed. Since its really hard to tell over a forum you might want to take her to a vet to have it checked anyhow, although to me it does look like and from what you described that shed was stuck and constricted circulation, it could be something else, and its best to have it checked out if you are uncertian.
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reiko 

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