It may just be a case study, but it's a great place to start. Many people suffer from panic attacks, especially chronic panic attacks. Even though she had been prescribed medication, she saw no relief. Following her adjustments it was noted that her panic attacks decreased and she experienced positive changes in blood pressure.
An excerpt from the case study:
"A 52-year-old female diagnosed with chronic panic attacks. She had been prescribed a variety of antidepressants and tranquilizers over the years, as well as undergoing counseling and relaxation training - all to no benefit. Chiropractic examination revealed areas of upper and mid cervical, upper and mid thoracic and right sacroiliac fixations. The patient's blood pressure would read 182/102 mm Hg and her pulse rate 120 beats per minute during an attack. Her blood pressure would drop to 140/80 and her pulse to 76 beats per minute four minutes after the adjustment. She had been free of panic attacks for more than two months which is the best she had been in years in spite of the fact that her M.D. cut her Xanax dosage in half after she began chiropractic care. "
Potthoff S. Penwell B, Wolf J. ACA J of Chiropractic, 1993 (December) 30:26-28.