Abstract

OBJECTIVE:

We report the first randomised controlled trial (RCT) using a combination of St. John's wort (SJW) and Kava for the treatment of major depressive disorder (MDD) with comorbid anxiety.

METHODS:

Twenty-eight adults with MDD and co-occurring anxiety were recruited for a double-blind RCT. After a placebo run-in of 2 weeks, the trial had a crossover design testing SJW and Kava against placebo over two controlled phases, each of 4 weeks. The primary analyses used intention-to-treat and completer analyses.

RESULTS:

On both intention-to-treat (p = 0.047) and completer analyses (p = 0.003), SJW and Kava gave a significantly greater reduction in self-reported depression on the Beck Depression Inventory (BDI-II) over placebo in the first controlled phase. However, in the crossover phase, a replication of those effects in the delayed medication group did not occur. Nor were there significant effects on anxiety or quality of life.

CONCLUSION:

There was some evidence of antidepressant effects using SJW and Kava in a small sample with comorbid anxiety. Possible explanations for the absence of anxiolysis may include a potential interaction with SJW, the presence of depression, or an inadequate dose of Kava.