Botanicals are an alternative option to prescription drugs for the alleviation of symptoms due to anxiety disorders and insomnia. Melissa officinalis L. has been shown as an anti-stress and anxiolytic agent. We previously reported moderate stress improvement in mice in which Cyracos(®), a standardized Melissa officinalis L. extract, was administrated. Cyracos(®) contains phytochemicals that inhibit gamma-aminobutyric acid catabolism. This was a prospective, open-label, 15-day study to evaluate the efficacy of Cyracos(®) on stressed volunteers, who have mild-to-moderate anxiety disorders and sleep disturbances. Using clinician rating criteria, primary outcomes showed improvement of symptoms. Cyracos(®) reduced anxiety manifestations by 18% (p < 0.01), ameliorated anxiety-associated symptoms by 15% (p < 0.01) and lowered insomnia by 42% (p < 0.01). As much as 95% of subjects (19/20) responded to treatment, of which 70% (14/20) achieved full remission for anxiety, 85% (17/20) for insomnia, and 70% (14/20) for both. Our study demonstrates, for the first time that chronic administration of Melissa officinalis L. relieves stress-related effects. It is critical that further studies incorporate a placebo and investigate physiological stress markers.