Herbal medicinal products have been traditionally used for the treatment of minor sleep disorders and mild anxiety symptoms. However, prospective clinical studies are scarce, due to a number of variability factors such as population heterogeneity and a strong placebo effect. To overcome these limitations, animal models are available that provide unbiased scientific results.

In this study, we examined the effect of an association of four compounds [namely Melissa officinalis, Crataegus oxyancantha, calcium lactate and magnesium thiosulfate (32/30/32/6; w/w)], on several behavioral tests in rodents. Animals were tested for general activity on an automated actimetry system, and for anxiety on the so-called “staircase test”.

In the actimetry test, adult mice were placed in an empty cage and their spontaneous level of activity (distance travelled and the number of rearings) was measured after an intraperitoneal administration of 25, 50 or 75mg/kg of the association. A dose-dependent decrease of the distance travelled and number of rearings was observed after administration (statistically significant at the dose of 75mg/kg). In the staircase test, the number of rearings (a measure of anxiety) and the number of steps climbed (general activity) were measured. A statistically significant decrease in the number of rearings was observed at the dose of 25mg/kg (compared to vehicle-treated animals), whereas no effect in the number of steps climbed was observed at the same dose. These results suggest that the association could induce an anxiolytic effect. At higher doses, a sedative effect was observed.

In conclusion, the administration of an association of Melissa officinalis, Crataegus oxyacantha, calcium and magnesium induced a clear dose-dependent sedative effect in mice. One test suggests that this association could also have anxiolytic properties. This study confirms that herbal medicinal products could be a beneficial treatment for minor sleep disorders or mild anxiety symptoms.