Melissa officinalis (lemon balm) is contemporaneously used as a mild sedative and/or calming agent. Although recent research has demonstrated modulation of mood in keeping with these roles, no studies to date have directly investigated the effects of this herbal medication on laboratory-induced psychological stress.
In this double-blind, placebo-controlled, randomized, balanced crossover experiment, 18 healthy volunteers received two separate single doses of a standardized M. officinalis extract (300 mg, 600 mg) and a placebo, on separate days separated by a 7-day washout period. Modulation of mood was assessed during predose and 1-hour postdose completions of a 20-minute version of the Defined Intensity Stressor Simulation (DISS) battery. Cognitive performance on the four concurrent tasks of the battery was also assessed.
The results showed that the 600-mg dose of Melissa ameliorated the negative mood effects of the DISS, with significantly increased self-ratings of calmness and reduced self-ratings of alertness. In addition, a significant increase in the speed of mathematical processing, with no reduction in accuracy, was observed after ingestion of the 300-mg dose.
These results suggest that the potential for M. officinalis to mitigate the effects of stress deserves further investigation.
From the Human Cognitive Neuroscience Unit, Division of Psychology, University of Northumbria, Newcastle upon Tyne, NE1 8ST UK.
Address correspondence and reprint requests to David O. Kennedy, Human Cognitive Neuroscience Unit, Division of Psychology, University of Northumbria, Newcastle upon Tyne NE1 8ST, UK. E-mail: email@example.com
Received for publication November 6, 2003; revision received February 2, 2004.