Article révisé par les pairs
Résumé : Working on ants as models, the most consumed anxiolytic, alprazolam, has been shown to have adverse effects. We presumed that plant extracts might be a safe alternative. A product made of an extract of Valeriana officinalis L., Humulus lupulus L., Passiflora incarnata L., and Ballota nigra L., easily available in any drugstore, was tested in the same way alprazolam had been. Contrary to alprazolam, this product did not significantly alter the ants? brood caring, cognition, behaviour in front of nestmates, tactile perception, learning and memory. It efficiently calmed the ants which often rested but not fully slept, avoided risky tasks and quietly reacted in a stressing situation. Adaptation occurred for the few adverse effects of this product (large sinuosity of movement, what had an effect on some behaviour).No habituation occurred as for its calming effect and it did not lead to dependence contrary to alprazolam. After its consumption ends, the calming effect of the plant extract slowly vanishes in 29 hours, step by step. In conclusion, this extract appears to be a safe product for reducing anxiousness and should be used preferentially to synthetized compounds which are known to have severe adverse effects.