Lactate vulnerability of remitted panic patients.

Sodium lactate precipitates panic in 70-100% of clinically ill patients with panic disorders. The lactate vulnerability of remitted patients is unknown. In this study, 13 panic patients completed three sequential sodium lactate infusions: one before treatment, a second when panic free on tricyclic antidepressants (TCA), and a third when in remission and unmedicated for 1 to 6 months. Three out of 13 patients panicked at the third infusion as compared to 0/13 infused on TCA and 7/12 at pretreatment infusion. This result (1) indicates that lactate vulnerability can exist in clinically well, unmedicated patients, and (2) raises the possibility that lactate vulnerability may be a trait characteristic. Further studies are needed before definite conclusions can be drawn.