Table 4.

Summary of some clinical trials conducted on Senna spp.

Samples	Type of study/findings/results	Country	Ref
Senna alata (L.) Roxb.	Randomized controlled trial Trial registration: TCTR0180828004 Evaluating the use and safety of S. alata on bowel function recovery among women with gynecologic cancer 90 women candidates diagnosed with gynecologic cancer were randomly assigned to postoperative consumption (45 with S. alata tea and 45 with warm water) Usage of S. alata significantly reduced the time of first passage of flatus (mean difference: -8.5 h; 95% confidence interval: -3.7, -13.4 h) and time of first defecation (mean difference: -19.8 h; 95% confidence interval: -11.2, -28.5 h) compared with the controls The use of S. alata showed a positive impact during the postoperative care of gynecologic cancer patients	Thailand	[231]
Senna	Randomized controlled and crossover study Assessing the efficacy and safety of Senna versus polyethylene glycol in treating constipation in children The proportional formula was used to calculate the sample size and 28 patients were obtained Effectiveness of laxative therapy was evaluated by mean of a three-variable construct (a) Daily bowel movement (b) Faecal soiling (c) S clean abdominal X-ray The study was completed before the time because an interim analysis showed effective results of Senna (p = 0.026) The maximum daily dose of Senna and polyethylene glycol was recorded as 38.7 mg and 17 g Senna therapy showed promising results against constipation in children with anorectal malformation	Mexico	[232]
Senna	Comparative study Evaluating of Senna and other oral bowel medicines for treating constipation in pediatric oncology patients getting opioids The results of 5-year investigation demonstrated that 41.8% (n = 245) had blood cancer, 50.3% (n = 295) had solid cancer, and 7.9% (n = 46) had brain cancer out of 586 matched samples (age: 0-20 years, ave. age: 11.5 years) Initializing Senna therapy, over another oral bowel medication, reduced the subsequent risk of surrogate markers of problematic constipation. Adjusted effect of Senna on enema (hazard ratio, 0.31; 95% confidence interval, 0.11-0.91), abdominal radiographic imaging (hazard ratio, 0.74; 95% confidence interval, 0.55-0.98), and escalation of oral bowel medicine (hazard ratio, 0.78; 95% confidence interval, 0.59-1.03) were recorded	Philadelphia	[233]
Senna	Control single-blinded randomized study Assessing the efficacy and safety of gum chewing added to high dose Senna before colonoscopy promotes bowel cleaning 129 candidates participated and were further divided into two groups (a) n = 65 patients treated with Senna solution (150 mL) and sennoside tablet (80 mg) daily for 3 days before the colonoscopy (b) n = 64 patients were additionally advised to chew sugarless gum half an hour (three times) daily for 3 days The results demonstrated that gum chewing enhanced colonoscopy bowel preparation quality and is considered a physiologically sound, safe, and impassive part of the colonoscopy bowel preparation. The gum chewing group showed better cleaning compared to other groups	Turkey	[234]
Senna	Placebo-controlled, double-blinded, randomized study Evaluating the use of Senna with docusate for constipation after pelvic surgery 96 candidates completed a baseline seven-day bowel diary pre- and postsurgery. After pelvic surgery, candidates were divided into two groups: (a) n = 45 in the placebo group and (b) n = 48 in Senna (8.6 mg) with docusate (50 mg) group. The findings demonstrated that the use of Senna with docusate decreases the time to first bowel movement in those undergoing pelvic surgery than placebo (3.00 vs. 4.05 days; p = 0.001).	Philadelphia	[235]
Senna	Case study Case of a 31-year-old female patient who, after prolonged ingestion of Senna extract, developed severe weight loss, cyclic oedema, and dyspepsia, accompanied by an asymptomatic increase in markers of liver and muscle damage, dyslipidemia, electromyographic alterations, and mitochondrial myopathy in the muscle biopsy This clinical case is of particular significance, given that Senna is widely used for its pharmacological properties, with failure to consider its potentially toxic effects	Portugal	[236]
Senna	Single-blinded randomized study The effectiveness of Senna tables and sodium phosphate solution for bowel preparation before colonoscopy was examined for its efficiency A total of 134 candidates were treated with Senna tablets (180 mg) and sodium phosphate solution (95 mL) on the day before colonoscopy The results demonstrated that the mean cleanliness scores in the four segments of the colon (rectum, sigmoid segments, descending colon, and transverse colon) except the cecum were higher in the sodium phosphate group than in the Senna group (7.9 vs. 8.3, 8.0 vs. 8.5, 7.9 vs. 8.5, 7.9 vs. 8.2, and 7.2 vs. 6.9, respectively) The taste of Senna was more effective compared to sodium phosphate solutions	Thailand	[237]
Senna tora (L.) Roxb.	Experimental study Supplementation of S. tora fibre on the serum lipid profile of diabetic Korean patients was evaluated. S. tora fibre supplement of a combination of soluble fibre extracted from S. tora (2 g), alpha-tocopherol (200 mg), ascorbic acid (500 mg), and maltodextrin (300 mg) was prepared in a pack and given to a total of 15 candidates 2 packs per day up to 2 months The results demonstrated that S. tora fibre products were safe for consumption and additionally provided the necessary amount of dietary fibre for helping in the maintenance of lipid status in diabetic (type II) patients	Korea	[238]
Senna	Controlled randomized single-blinded study Evaluating efficiency and acceptability of high dose Senna tablets and its comparison with standard polyethylene glycol in adult patients 192 patients participated and were treated into two groups: (a) n = 91 in polyethylene glycol group and (b) n = 101 in Senna group The Senna tablet group showed acceptable results for colon cleansing and tolerance compared to the polyethylene glycol group (p < 0.001)	—	[239]
Senna	Controlled study Highly purified Senna extract was evaluated against cell proliferation, crypt length in the entire colon and gene expression (p53 and bcl-2). 171 patients (84 with sennoside-containing syrup and 87 without sennoside-containing syrup) were included 15 patients with Senna and 17 without Senna from 32 randomized patients were used for biopsies Proliferation activity in four areas of colon and gene expression (p53 and bcl-2) was evaluated by using 5-bromo-2′-deoxyuridine labelling, immunohistochemistry, and immunohistochemical The results demonstrated that crypts were shorter in the Senna group than without Senna group in the transverse and sigmoid colon. In the entire colon, the labelling index was higher in the Senna group than without the Senna group. In addition, bcl-2 expression was higher in both groups when crypts were shorter and proliferation was enhanced while no difference was recorded in p53 expression	Netherlands	[240]
Senna and MaZiRenWan (MZRW) (1st phase)	A double-blinded, double-dummy, randomized, and controlled trial Trial registration: NCT01695850 The protocol evaluated the effectiveness of MaZiRenWan (MZRW) with laxative Senna for functional constipation 291 candidates were recruited, and after a 2-week run-in period, the suitable candidates were randomly grouped into the three viz (a) Chinese medicine arm (MZRW and western medicine placebo) (b) Western medicine arm (Senna and Chinese medicine placebo) (c) Placebo arm (Chinese medicine placebo and western medicine placebo) The results of the eight-week treatment showed the increased responder rate for a complete spontaneous bowel movement (CSBM≧1/week) in the course of the treatment while the eight-week follow-up period showed changes of colonic transit, individual and global symptom assessments, and adverse effects	China	[241]
Senna and MaZiRenWan (MZRW) (2nd phase)	A double-blind, double-dummy, randomized, and controlled trial Trial registration: NCT01695850 Evaluating the efficacy and safety of Chinese herbal medicine MZRW and its comparison with the stimulant laxative Senna and placebo against functional constipation Primary and secondary outcomes demonstrated that the MZRW showed well-accepted effects in increasing complete spontaneous bowel movement per week compared to the Senna group (68.0% vs. 57.7%, with p = 0.14) during the treatment. After the eight-week-follow-up period, 47.4% of patients had a complete response to MZRW, 20.6% had a complete response to Senna, and 17.5% had a complete response to placebo (p < 0.005 for MZRW vs. placebo)	China	[242]