Clinical Efficacy of Bitter Orange Aromatherapy for Premenstrual Syndrome
Premenstrual syndrome (PMS) affects up to 40% of reproductive-age women worldwide. PMS symptoms include irritability, depression, anxiety, sleep disorders, and bloating in the days before menstruation begins. Bitter orange (Citrus × Aurantium, Rutaceae) has traditionally been used as a carminative, antiemetic, antidepressant, anxiolytic, analgesic, and sedative and to treat headache, inflammation, insomnia, and uterine prolapse. Previous clinical studies have shown aromatherapy with essential oils (EO) from bitter orange flowers can reduce stress and menopausal symptoms in postmenopausal women and reduce pain and anxiety in women in labor. The purpose of this randomized, double-blind, placebo-controlled trial was to evaluate the effects of bitter orange EO aromatherapy on PMS symptoms in young women.
The trial was conducted at the Shiraz University of Medical Sciences in Shiraz, Iran from March 2016 to February 2017 with female medical students from the university. Participants were included if they had moderate to severe PMS symptoms (scores > 20 on the Premenstrual Symptoms Screening Tool [PSST]) and normal mental health (scores < 23 on the Goldberg General Health Questionnaire [GHQ]), were not using vitamin supplements, had not used hormonal medications in the previous two months, had a menstrual cycle of 24-35 days, and had no underlying diseases such as thyroid disease or diabetes. Participants were excluded if they had experienced a stressful event such as bereavement, marriage, or surgery during the previous three months, had a stressful event during the trial, had changes in their menstrual cycles during the trial, used medications, or had a sensitivity to the oils used in the trial.
Participants were randomly assigned to receive either aromatherapy with bitter orange EO or odorless sweet almond (Prunus dulcis, Rosaceae) oil, which was used as a placebo. Pure bitter orange flower EO was obtained from Barij Essence and Adonis Gol Darou (Tehran, Iran). [Note: While the authors used “bitter orange” to describe the essential oil, oils derived from the flowers are called neroli.] The bitter orange EO was prepared at a 0.5% concentration for inhalation. The source of almond oil was not provided. Participants were instructed to place 10 drops of oil on an eye pad, place the pad 30 cm (11.8 inches) away from the nose, and breathe normally in a quiet setting for five minutes. Aromatherapy was performed twice daily for five days, beginning about one week before menstruation, for two consecutive cycles. Participants completed the PSST at baseline and after each aromatherapy intervention.
A total of 66 participants were randomized, with 33 in the bitter orange group and 33 in the placebo group. Two participants in each group dropped out of the trial. Three dropped out because of a lack of willingness to continue their participation, and one dropped out because of medication use. There were no significant differences in demographic and physical characteristics between the groups at baseline. Mean total PSST scores decreased (improved) from baseline to cycle two in both groups; however, an improvement was statistically significant only in the bitter orange group (P = 0.001). Mean scores were better in the bitter orange group compared to the placebo group after the first cycle (22.64 versus 28.06, respectively; P = 0.003) and second cycle (22.09 versus 29.19, respectively; P = 0.001). Mean scores from the PSST, representing psychological PMS symptoms, decreased in both groups but were lower in the bitter orange group compared to the placebo group after one and two cycles (both P ≤ 0.003). Mean scores for physical PMS symptoms did not change significantly in either group. There was a nonsignificant decrease in mean scores for social function symptoms in the bitter orange group and an increase in mean scores for the placebo group after the second cycle (P = 0.034). No participants reported any adverse events.
The authors state this is the first trial of bitter orange EO aromatherapy in young women with PMS. Medical students who used aromatherapy for five days before menstruation reported a reduction in PMS symptoms, with the greatest impact on psychological symptoms. A possible cause of PMS is reduced activity of the parasympathetic nervous system, and the authors hypothesize bitter orange aromatherapy improves psychological PMS symptoms by increasing parasympathetic activity. Additional trials are needed to further evaluate the effects of bitter orange EO aromatherapy on physical PMS symptoms. Future trials should enroll more participants, enroll a broader segment of the female population, and increase the duration of the intervention to study to access longer-term effects.
The authors declare no conflicts of interest.
Heydari N, Abootalebi M, Jamalimoghadam N, Kasraeian M, Emamghoreishi M, Akbarzadeh M. Investigation of the effect of aromatherapy with Citrus aurantium blossom essential oil on premenstrual syndrome in university students: A clinical trial study. Complement Ther Clin Pract. August 2018;32:1-5. doi: 10.1016/j.ctcp.2018.04.006.