Lactate infusions: the role of baseline anxiety

Sodium lactate infusions provoke panic symptoms in patients with panic attacks at a greater rate than in normal controls. The effect of the baseline, preinfusion state on subsequent response to lactate is the subject of debate. Baseline symptoms, anxiety levels, and autonomic arousal and subsequent response to lactate were examined in 44 panic patients and 10 normal controls. Patients who had a typical panic attack with lactate had higher baseline symptom ratings, but these did not fully account for differences in response to lactate. Although baseline measures are not the sole determinant of response to lactate infusion, they may be one factor influencing how readily a patient reaches the threshold for a panic attack.