Depression, with a prevalence of 15-20%, is one of the most common psychological disorders, which can result in diminution of the individual’s performance in various personal and social areas, adhedonia and emotional distress. According to DSM IV, symptoms of Major Depressive Disorder (MDD) include: depressive mood along with sleep disorders; reduction in desire/pleasure; feelings of guilt or worthlessness; alteration in energy level/fatigue; impaired concentration/attention; alteration in appetite/weight; motor psychological disorders and suicidal thoughts. To diagnose MDD, it is necessary that depressive mood and reduction in desire/pleasure manifest themselves along with 4 other symptoms for at least 2 weeks and not be due to mourning. Depressive disorders are usually chronic and recurrent and up to 70% of the patients with one episode of major depression will experience another episode. Also, when antidepressant medication is discontinued, clinical observation needs to go on, depending on every patient’s condition.
In a study of the antidepressant effect of rose geranium essential oil on mice, oral administration of this essential oil with concentrations of 0.5 to 2% reduced the immobility time in the forced swimming test (p<0.0001) and intraperitoneal injection of reserpine with a dose of 5 mg/kg weight of the animal, 18 hours before administration of rose geranium essential oil significantly antagonized the suppressive effect of the oral essential oil (1.5% concentration). The results of this study confirmed the antidepressant properties of rose geranium essential oil and proposed presynaptic mechanisms for the manifestation of its antidepressant effect.
In a double-blind clinical trial, 81 patients of 18-50 years of age with depression were randomly divided into 3 groups: fluoxetine capsule (20 mg daily) and placebo drop; geranium oral drop 10% (20 drops, 2 times a day) and placebo capsule; geranium oral drop 5% (20 drops, 2 times a day) and placebo capsule. The duration of the study was 12 weeks and the patients were examined at the beginning of the study, every 2 weeks and at the end of the study, using interview, clinical examination and Beck test. According to the results of this study, although geranium 10% caused statistically significant reduction in Beck test scores in the 3rd and 4th stages of the study (p<0.03), due to its unpleasant flavor, the rate of drop-out was significantly higher in this group in comparison with other groups (p<0.001). Also, in all stages of examination, geranium drop 5% was more effective than fluoxetine capsule. Percentage of recovery with geranium drop 5% was reported as 90.9% (in comparison with 71.4% improvement with fluoxetine) and this difference was statistically significant (p=0.05).