Background: One of the most common psychiatric disorders that adversely affects quality of life and functioning is Major Depressive Disorder. Given the side effects of antidepressants, medicinal plants have attracted attention in recent years, and animal studies have revealed the antidepressant effects of Cinnamomum zeylanicum essential oil. The study is aimed at investigating the effect of this essential oil on treatment of patients with MDD treated with fluoxetine.
Methods: In this double-blind clinical trial, 60 patients were randomized to three groups of 20 each: fluoxetine (20mg) +placebo daily, fluoxetine (20mg) +5 oral drops of Cinnamon essential oil daily, and fluoxetine (20mg) +15 oral drops of Cinnamon essential oil daily. At baseline and the weeks 2, 4, 6 and 8, a checklist of drug side effects and Beck Depression Inventory (BDI) was completed by all the patients. Data were analyzed by the SPSS 21.
Results: The mean (±standard deviation) score on BDI at baseline was 32.50±9.37 in fluoxetine+placebo group, 26.31±7.21 in fluoxetine+C. zeylanicum (5 drops) group, and 31.45±10.01 in fluoxetine+C. zeylanicum (15 drops) group. In the week 2 of treatment, the mean (±standard deviation) score on BDI was 26.90±8.36 in fluoxetine+placebo group and 18.36±4.62 in fluoxetine+C. zeylanicum (5 drops) group, representing a significant decrease (p<0.01) due to treatment with C. zeylanicum, but the score on BDI was not significantly different between fluoxetine+C. zeylanicum (15 drops) group (22.65±9.32) and the other two groups. In the weeks 6 and 8 of treatment, treatment with fluoxetine and C. zeylanicum (5 and 15 drops) caused a significant decrease in BDI score when compared to fluoxetine+placebo group (p<0.01). There was no significant difference in sexual and gastrointestinal complications and weight changes among three groups.
Conclusion: Cinnamon essential oil caused improvement of MDD but this effect was not dose dependent