Lavender and Dodder Syrup Appears as Effective as Citalopram for Depression with Anxiety in Adults

Affecting 350 million people globally, major depressive disorder (MDD) is a chronic illness with a lifetime prevalence rate of 17% per individual. Comorbid anxiety can increase its severity. To treat this co-occurrence, selective serotonin reuptake inhibitors or serotonin-norepinephrine reuptake inhibitors are generally prescribed; however, half of patients using such drugs fail to respond due to adverse effects. The use of natural therapeutics has become a popular alternative. Lavender (Lavandula angustifolia, Lamiaceae) flower and dodder (Cuscuta chinensis, Convolvulaceae) seed, two herbs with a history of combined use in Persian medicine have demonstrated anxiolytic and antidepressive properties in previous trials. These authors designed a study to compare the effects of a syrup containing lavender flower and dodder seed extracts to the reference drug citalopram on patients with moderate MDD and comorbid anxiety.

The six-week, double-blind, double-dummy, randomized, placebo-controlled trial was conducted at the Isfahan Neuropsychiatric Outpatient Clinic, Kashani Hospital, affiliated with the Isfahan University of Medical Sciences (Tehran, Iran), and took place from April 2017 to June 2018. All study materials were sourced from businesses in Tehran. Citalopram was obtained from the Sobhan Daru Company and identical-appearing placebo tablets were obtained from Behruz Pharmaceutical Company. Herbs were obtained from a local herbal store then verified and assigned a voucher number by the herbarium of the School of Pharmacy, Tehran University of Medical Science. The syrup was formulated and manufactured by the same School of Pharmacy. Fifteen grams of each herb were dried, ground, then water-extracted (400 mL total distilled water). Finally, a simple oxymel (34 mL) from Somayeh Company was added to the strained liquid mixture. Simple oxymel was used as placebo syrup and had the same smell, taste, and color as the herbal syrup due to the strong smell and taste of oxymel.

Participants were adults aged 18-60 years who had been referred to the Isfahan Neuropsychiatric Outpatient Clinic. Diagnosed with mild to moderate MDD with anxious distress by a psychologist, eligible patients scored < 24 on the Hamilton Anxiety Rating Scale (HAM-A) and ≥ 18 on the Hamilton Depression Rating Scale (HAM-D). Exclusion criteria were as follows: suspected mental conditions other than MDD and anxious distress; use of psychotropic medication during the past 14 days; unstable conditions including liver or kidney failure; chronic conditions such as hypothyroidism, diabetes, or bleeding disorders; pregnant or breastfeeding; women of reproductive age not using contraception; substance abuse or addiction during the past three months; electroconvulsive therapy during the past three months; psychotherapy during the past month; suicidal tendency during the past year or scores > 2 on the suicide item of HAM-D; history of allergy to lavender, dodder, or citalopram.

A total of 56 adults met all criteria and were evenly randomized to either the intervention group (placebo tablet plus herbal syrup) or the conventional treatment group (citalopram tablet plus placebo syrup). Both groups received one 20 mg tablet daily and one dose (5 mL) of syrup every 12 hours for six weeks. Mean age was 38.6 ± 6.6 years in the conventional group and 36.1­ ± 9.2 in the intervention group. Women comprised 80% (n = 40) of total participants and were evenly divided between groups. Three patients from each group withdrew by week three due to exacerbated gastritis (n = 1) and consent withdrawal (n = 2) from the conventional group, and for being unreachable (n = 3) from the intervention group.

Changes in HAM-D demonstrated that the mean score of depression was significantly decreased in both groups at week six (P < 0.001 for both); however, the difference in decrease between groups was not significant. For HAM-A, there was a decrease in anxiety scores in both groups, with the herbal syrup having a greater reduction than citalopram by week six (P = 0.004). It was also observed that time and intervention had an interaction (P = 0.006). Remission rates did not differ between groups according to HAM-D; however, according to HAM-A, anxiety remission rates at the end of the study were higher in the herbal syrup group than in the citalopram group (68% vs 28%; P = 0.01). Adverse effects reported included drowsiness in both groups, nausea and constipation in the herbal syrup group, and decreased libido, headache, and xerostomia in the citalopram group.

The authors suggest that lavender and dodder syrup is as effective as citalopram for reducing depression with anxiety; however, further studies with larger sample sizes and longer durations are needed. A previous HerbClip1 found both lavender and dodder were beneficial in conjunction with antidepressants. These herbs combined may be a consideration for adults affected by MDD, especially those with comorbid anxiety. Further research on the best preparation and administration is needed to ensure consistent results. The authors report no conflicts of interest.

Reference

1Oliff HS. Herbal Remedies for Psychiatric Conditions. HerbClip. January 15, 2019 (No. 051853-608). Austin, TX: American Botanical Council. Review of Herbal Medicines in the treatment of psychiatric disorder: 10 year updated review by Sarris J. Phytother Res. 2018;32(7):1147-1162. doi: 10.1002/ptr.6055.

Firoozeei TS, Barekatain M, Karimi M, Zargaran A, Akhondzadeh S, Rezaeizadeh H. Lavender and dodder combined herbal syrup versus citalopram in major depressive disorder with anxious distress: A double-blind randomized trial. J Integr Med. September 2020;18(5):409-415. doi: 10.1016/j.joim.2020.06.002.