Chai Hu Long Gu Mu Li Wan & Gu Pi Wan

First you should read What Does Acupuncture Treat? to better understand how acupuncture approaches treating collections of symptoms (or diagnostic patterns) vs. western "conditions" like panic disorder. You should, of course, consult with a licensed practitioner in your area to ask these questions. Trying to treat yourself can be dangerous but at least it can be counterproductive and take longer than it should. Herbal Medicines in particular are more of a moving target than a formula = condition treatment.

Second, read the practitioner level information for both Gui Pi Wan and Chai Hu Long Gu Mu Li Wan. There are any number of TCM diagnostic patterns that can be involved with panic disorder and associated symptoms - proper diagnosis is key to effective treatment. The practitioner level pages show which formulas are -commonly- related to each formula.

Finally read the page on Da Huang for more information on how it is used and what formulas it appears in.