Specificity of lactate response in panic disorder, panic with concurrent depression and major depression

Lactate infusions with 0.5 molar sodium lactate in a dose of 10 ml/kg within 20 min were given to patients with panic disorder (n = 6), panic attacks with concurrent major depression (n = 7) and major depression without panic (n = 5). Lactate-induced anxiety and symptom attacks without panic were seen more often in the groups with panic attacks, but a full-blown panic attack was provoked in only four subjects, all belonging to the groups with a history of panic attacks. The low incidence of lactate-induced panic attacks can be explained by differences in the procedure that aimed at reducing expectancy biases and baseline anxiety.