Chinese Herbal Sachet Inhalation for Primary Dysmenorrhea in Female College Students

Overview

Primary dysmenorrhea (painful menstrual periods without an underlying disease) is very common in female college students and can affect sleep, mood, study and daily life. This study tested whether sleeping next to a traditional Chinese herbal sachet - a small cloth bag containing a standardized blend of 13 aromatic herbal materials chosen by an expert consensus (Delphi) process - reduces menstrual pain and menstrual symptoms, and improves anxiety and depression, compared with an identical-looking placebo sachet. Eighty-two female students at Sichuan Nursing Vocational College with primary dysmenorrhea were randomly assigned to the herbal sachet or the placebo sachet. Participants placed the sachet within about 30 cm of the head every night during sleep for 9 weeks, with a fresh sachet every 3 weeks; both groups received the same health education. Pain (visual analogue scale), menstrual symptoms (Cox Menstrual Symptom Scale), anxiety (Self-Rating Anxiety Scale) and depression (Self-Rating Depression Scale) were measured before and within one week after the 9-week intervention. Participants did not know which sachet they received.

Design: single-centre, randomized, single-blind (participant), placebo-controlled, two-arm parallel-group trial. Randomization: participants were numbered in order of recruitment and allocated 1:1 using a computer-generated random number table (SPSS). Intervention: herbal sachet containing Angelica dahurica root 5 g, Syzygium aromaticum flower bud 5 g, Artemisia argyi leaf 5 g, Foeniculum vulgare fruit 5 g, Kaempferia galanga rhizome 5 g, Cinnamomum cassia bark 10 g, Angelica sinensis root 10 g, Ligusticum chuanxiong rhizome 10 g, Cyperus rotundus rhizome 10 g, Aucklandia lappa root 10 g, Rosa rugosa flower bud 15 g, Osmanthus fragrans flower 15 g and Liquidambar orientalis resin 0.1 g, ground to powder and sealed in a non-woven bag inside a mesh pouch. The formula was developed through a three-round Delphi expert consensus process. Placebo: sachet of identical appearance and weight containing whole-wheat flour, lily, chrysanthemum and orange-peel powder. Procedure: both sachets were hung at the head of the bed within 30 cm of the nose from about 23:00 to 07:00 nightly for 9 weeks and replaced every 3 weeks; adherence was supported by a daily calendar record and nightly WeChat reminders. Both groups received the same health education on primary dysmenorrhea. Sample size: based on a previously reported VAS effect (effect size 0.88, alpha 0.025 two-sided, power 0.90), 68 participants were required, increased by 20% for attrition to 82. Analysis: within- and between-group comparisons using t-tests or Mann-Whitney/Wilcoxon tests as appropriate. Safety: participants inhaled the sachet for 5 minutes and were observed for 10 minutes when it was first issued; adverse reactions were monitored throughout.