The Effectiveness of Aromatherapy for Depressive Symptoms: A Systematic Review

Table 3

Description of the interventions and protocols used in the selected studies.

Reference	Intervention and protocol
	Comparison group ()	Treatment group(s) ()	Type of essential oil used	Duration of the study	Administration method	Treatment frequency	Duration per session	Total number of sessions
Inhalation aromatherapy
[18]	Control with sweet almond cold-pressed pure vegetable oil with no fragrance (NA)	(i) Carrier oil with fractionated low (NA) grade essential oil; (ii) Pure essential oil (NA)	(i) Fractionated oils of unknown purity diluted 1 : 3 in carrier oil; (ii) Mixture of lavender, bergamot, and cedarwood (2 : 1 : 1)	8 weeks	3 drops of oil applied to a bib worn during the administration of the treatment	Daily	15–20 min	56
[19]	Control, jojoba oil (14)	(i) 2% dilution of a mixture of essential oils (6)	(i) 0.25 rose otto essential oil and 0.75 lavender, 2% dilution of the essential oil mixture	4 weeks	8 drops of oil applied to a cotton pad. Subjects were instructed to smell the cotton pad for 15 min	Twice a week	15 min	8
[20]	Control, no intervention (6)	(i) Pure essential oil (7)	(i) Lavender; (ii) Petitgrain; (iii) Bergamot	1 day	5 drops of oil applied on a filter placed in a diffuser	Once	5 min	1
[21]	Control, water (20)	(i) Pure essential oil (20)	(i) Yuzu	2 days	10 L oil in a cotton pad used in a diffuser set in the subject’s nostrils	Twice	10 min (sessions separated in intervals around 2.6 days)	2
[22]	Control group which did not receive any nonpharmacological method for pain relief of labor (160)	(i) Nonpharmacological methods for pain relief of labor including showering, being in upright position, aromatherapy, and soft music without words (160)	(i) 20% lavender essential oil	During labor	10 × 10 cm cloth impregnated with 1 mL 20% lavender essential oil which was attached to the mother’s breast at the beginning of the active phase. The aromatherapy intervention was combined with other nonpharmacological interventions	Once	Duration of the active phase of labor	1
Aromatherapy massage
[23]	Control, grape seed oil (16)	(i) Diluted essential oil (16)	(i) 9 essential oils (bergamot, lemon clary sage, lavender, roman chamomile, geranium, rose otto, sandalwood, and jasmine). A combination of essential oils chosen by the aromatherapist on each treatment session (16)	12 weeks	15 mL grape seed carrier oil with (4 drops) or without essential oils applied in a full body massage using gentle effleurage and petrissage	Once a fortnight	40 min	6
[24]	Control, no intervention (13)	(i) Aromatherapy massage (16); (ii) Massage with inert carrier oil (13)	(i) 1% lavender essential oil diluted in sweet almond oil	2 years	Back massage	Weekly	30 min	4
[25]	Usual supportive care	(i) Usual supportive care and aromatherapy massage	(i) 20 essential oils	10 weeks	Standardized massage agreed by the therapists	Weekly	1 h	4
[26]	Control, no intervention	(i) Aromatherapy massage	(i) 1% massage oil containing melissa, juniper, and rosemary essential oils mixed into jojoba oil (1 : 2 : 2 ratio)	8 weeks	Standardized massage on the back, shoulders, arms, hands, lower legs, and feet using 20–30 mL massage oil	Every two weeks	1 h	4
[19]	Control, essential oil blend unscented white lotion (14)	(i) 2% dilution of a mixture of essential oils (8)	(i) 0.25 rose otto essential oil and 0.75 lavender, 2% dilution of the essential oil mixture	4 weeks	Topic application of the oil or lotion on both hands with gentle strokes of homogeneous pressure and speed	Twice a week	15 min	8
[27]	Cognitive behavior therapy (19)	(i) Aromatherapy massage (20)	(i) 20 essential oils	2 years	Standardized massage combined with treatment as usual (routine support)	Weekly	1 h	Up to 8 sessions in 10 weeks
[28]	Control, no intervention (30)	(i) Aromatherapy massage (30); (ii) Massage (30)	(i) 3% oil mixture containing lavender, geranium, rose, and rosemary (4 : 2 : 1 : 1 ratio) in almond and evening primrose oil	4 weeks	Massage in the abdomen, tights, and arms using massage oil containing essential oils or odorless liquid petrolatum. Massage was applied with clockwise circular movements and light pressure	Twice a week	30 min	8
[29]	Control, no intervention (12)	(i) Aromatherapy massage (13)	(i) Jojoba oil containing 2% lavender and 2% geranium essential oils	4 weeks	Massage on the neck, shoulders, arms, back, and legs including effleurage, friction, petrissage, and vibration at a moderate pressure using 20 mL of massage oil	Twice per week	40 min	8

In this study, both aromatherapy modalities were tested, inhalation aromatherapy and aromatherapy massage. Therefore, the study was included in both categories in the table. NA, not available; min, minutes; h, hour.