The influence of ethanol infusion on the effects of 35% CO2 challenge. A study in panic disorder patients and healthy volunteers.

Unlabelled: Alcohol and panic disorders co-occur at a rate that exceeds chance significantly. Early experimental work suggests that alcoholic subjects, compared to non-alcoholics, are less sensitive to sodium lactate and that alcohol intake reduces the response to a 35% CO(2) challenge in Panic Disorder patients. The present study documents the direct pharmacological effect of ethanol infusion on CO(2) induced panic.
Methods: According to a placebo-controlled, double-blind, randomized, cross-over design 10 drug free panic disorder patients and 16 healthy volunteers underwent a 35% CO(2) challenge after intravenous infusion of a moderate dose of ethanol on one test day and of placebo on another test day.
Results: Compared to the placebo condition, the effect of the CO(2) challenge was significantly smaller after ethanol infusion (P = 0.041).
Discussion: A moderate dose of ethanol decreased the response to a 35% CO(2) without inducing pre challenge sedation.
Conclusion: The results comfort earlier findings of a direct pharmacological effect of ethanol on panic.