Raynbo
What happened to my message? Like Rescue Remedy...start a few days before and give it to her repreatedly up until the clipping... you can get in in cream form and rub it on her tummy...or a spray bottle in her mouth...or drops in the mounth. Put it in her drinking water too. No such thing as an overdose.
There are are also other flower essences that might be more specific to the problem you could try. Use em all.
Valerian Root ... 1/2 hour before. You can use that too. (How is she at taking capsules?) You could open them and mix them in a little raw meat...and down it goes....usually. My guess is 6 1/2 before ....
GAIA makes a tincture called Valerian Poppy Supreme...one dropper full in the mouth should do it. This is VERY effective stuff....but by dog standards, it dosent taste very good...you would have to be quick, and do it minutes before the clipping. This would work well with the Bach flowers...but use either it or the straight valerian. Valarian root is what they make valium out of.
You could go the chemical root and give her a valium....