Effects of tryptophan depletion on anxiety and on panic provoked by carbon dioxide challenge. Academic Article uri icon

abstract

  • Results of several studies suggest that anxiety is under serotonergic control. We studied the influence of tryptophan depletion on generalized anxiety and on the response to a 35% carbon dioxide (CO2) challenge. Fifteen healthy male volunteers received both a mixture of amino acids without tryptophan and a placebo mixture under double-blind conditions. The tryptophan-free mixture led to an 80% decrease in blood tryptophan levels compared to the placebo. There was a significant increase in anxiety on the Spielberger Anxiety Inventory and a trend towards more tension on the Profile of Mood States-'tension' items, both of which were interpreted as increased nervousness. Furthermore, a significant increase in neurovegetative panic symptoms occurred after the CO2 challenge. We conclude that the serotonergic system is causally involved in anxiety-related mechanisms and that it may be worth pursuing the role of tryptophan depletion on CO2-induced panic in patients with anxiety disorders.

published proceedings

  • Psychiatry Res

altmetric score

  • 8.5

author list (cited authors)

  • Klaassen, T., Klumperbeek, J., Deutz, N. E., van Praag, H. M., & Griez, E.

citation count

  • 79

complete list of authors

  • Klaassen, T||Klumperbeek, J||Deutz, NE||van Praag, HM||Griez, E

publication date

  • February 1998