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Introduction: Drotaverine, paracetamol, and peppermint oil are often prescribed for the treatment of gastrointestinal spasm and pain. This study aimed to evaluate the effect of these drugs alone and combined with the well-known antispasmodic hyoscine butylbromide on the human colon. Methods: Colon samples were obtained from macroscopically normal regions of 68 patients undergoing surgery and studied in muscle bath. Drotaverine, paracetamol, and peppermint oil were tested alone and in combination with hyoscine butylbromide on (1) spontaneous contractility induced by isometric stretch (in the presence of 1 µM tetrodotoxin) and (2) contractility induced by 10-5 M carbachol and after (3) electrical field stimulation-induced selective stimulation of excitatory (in the presence of 1 mM Nω-nitro-L-arginine and 10 µM MRS2179) and (4) inhibitory (under non-adrenergic, non-cholinergic conditions) pathways. (5) Drotaverine alone was also tested on cAMP-dependent pathway activated by forskolin. Results: Compared with the vehicle, drotaverine and paracetamol (10-9-10-5 M) did not modify spontaneous contractions, carbachol-induced contractions, and responses attributed to selective activation of excitatory pathways. The addition of hyoscine butylbromide (10-7-10-5 M), concentration-dependently reduced myogenic contractions and carbachol- and electrical field stimulation-induced contractile responses. The association of paracetamol (10-4 M) and hyoscine butylbromide (10-7-10-5 M) was not different from hyoscine butylbromide alone (10-7-10-5 M). At higher concentrations (10-3M-3*10-3 M), paracetamol decreased myogenic and carbachol-induced contractions. The adenylate cyclase activator, forskolin, concentration-dependently reduced contractility, leading to smooth muscle relaxation. The effect of forskolin 10-7 M was concentration-dependently enhanced by drotaverine (10-6M-10-5M). Discussion: Peppermint oil reduced myogenic activity and carbachol- and electrical field stimulation-induced contractions. The association of hyoscine butylbromide and peppermint oil was synergistic since the interaction index measured with the isobologram was lower than 1. No effect was seen on the neural-mediated inhibitory responses with any of the drugs studied although peppermint oil reduced the subsequent off-contraction. Drotaverine and hyoscine butylbromide have a complementary effect on human colon motility as one stimulates the cAMP inhibitory pathway and the other inhibits the excitatory pathway. Peppermint oil is synergic with hyoscine butylbromide suggesting that a combination therapy may be more effective in treating patients. In contrast, at therapeutic concentrations, paracetamol does not modify colonic contractility, suggesting that the association of paracetamol and hyoscine butylbromide has independent analgesic and antispasmodic properties.

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INTRODUCTION: Hyoscine butylbromide (HBB) is one of the most used antispasmodics in clinical practice. Recent translational consensus has demonstrated a similarity between human colonic motor patterns studied ex vivo and in vivo, suggesting ex vivo can predict in vivo results. It is unclear whether the mechanism of action of antispasmodics can predict different use in clinical practice. The aim of the present study is to bridge this gap dissecting HBB's role in excitatory and inhibitory neural pathways. METHODS: 309 colon samples from 48 patients were studied in muscle bath experiments. HBB was tested on: 1-spontaneous phasic contractions (SPCs); 2-carbachol-induced contractility; electrical field stimulation (EFS)-induced selective stimulation of 3-excitatory and 4-inhibitory pathways and 5- SPCs and EFS-induced contractions enhanced by neostigmine. Atropine, AF-DX116 (M2 blocker) and DAU-5884 (M3 blocker) were used as comparators. RESULTS: In the presence of tetrodotoxin (TTX), HBB and atropine 1 µM reduced SPCs. HBB and atropine concentration-dependently reduced carbachol- and EFS-induced contractions. Inhibitory effects of DAU-5884 on EFS-induced contractions were more potent than of AF-DX116. HBB did not affect the off-response associated to neural inhibitory responses. Neostigmine enhanced both SPCs and EFS-induced contractions. In the presence of TTX and ω-conotoxin (GVIA), neostigmine still enhanced SPCs. Addition of HBB and atropine reduced these responses. CONCLUSIONS: This study demonstrates that HBB inhibits neural cholinergic contractions associated to muscarinic (mainly M3) receptors. HBB has a potential role in reducing colonic spasm induced by the release of acetylcholine from enteric motor neurons and from an atypical source including a potential non-neuronal origin.

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Horses commonly receive hyoscine butylbromide (HB) prior to hospital admission for colic. This could alter the appearance of the small intestine (SI) on ultrasound scan and affect clinical decision making. The aim of this study was to assess the impact of HB on ultrasonographically assessed SI motility and heart rate. Six horses hospitalised for medical colic with no significant abnormalities on baseline abdominal ultrasound examination were included. Ultrasound was performed in three locations (right inguinal, left inguinal and hepatoduodenal window) before and at 1, 5, 15, 30, 45, 60, 90, and 120 minutes after intravenous injection of 0.3 mg/kg HB. Three blinded reviewers assessed SI motility using a subjective grading scale from 1 to 4, one being normal motility and four being no motility. Moderate interindividual and interobserver variability was observed, but none of the included horses developed dilated turgid loops of SI. Hyoscine butylbromide did not significantly reduce SI motility grade in any location (P = .60 left inguinal, P = .16 right inguinal, P = .09 duodenum). Heart rate (mean ± SD) was 33 ± 3 prior to HB injection and peaked at 71.3 ± 9 one-minute postinjection. Heart rate was significantly increased until 45 minutes (48 ± 9) after HB administration (P = .04). The appearance of dilated turgid SI loops common with strangulating intestinal lesions did not appear to develop following HB administration. Hyoscine butylbromide administered shortly before abdominal ultrasound examination would not be expected to affect clinical decision making in horses without small intestinal disease.

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BACKGROUND: Butylscopolamine (or hyoscine butylbromide, trade name Buscopan®) is occasionally administered as a premedication to reduce non-specific FDG uptake in the gastrointestinal tract based on its antiperistaltic effect. To date, there are no consistent recommendations for its use. The aim of this study was to quantify the reduction in intestinal and non-intestinal uptake by butylscopolamine administration and to derive relevance for clinical evaluation. RESULTS: 458 patients (PET/CT for lung cancer) were retrospectively reviewed. 218 patients with butylscopolamine and 240 patients without butylscopolamine had comparable characteristics. While the SUVmean in the gullet/stomach and small intestine was significantly reduced with butylscopolamine, the colon and rectum/anus showed no difference. The liver and salivary glands showed a reduced SUVmean, while skeletal muscle and blood pool were unaffected. An effect of butylscopolamine was particularly evident in men and patients under 65 years of age. There was no difference in the perceived confidence in the assessment of intestinal findings in the subjective evaluation, although in the butylscopolamine group further diagnostics appeared advisable more frequently. CONCLUSIONS: Butylscopolamine reduces gastrointestinal FDG accumulation only in selected segments and, despite a significant effect, only to a small extent. A general recommendation for the use of butylscopolamine cannot be derived from these results, its use for specific issues could be considered individually.

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BACKGROUND: Cardiovascular effects for drugs such as hyoscine butylbromide are poorly documented in the literature, unlike atropine, which is considered the antimuscarinic of choice in the presence of intraoperative bradycardia. AIM: The aim of the study was to describe the dose-related cardiovascular effect of hyoscine butylbromide in patients between 18 and 65 years of age, with low perioperative risk undergoing elective surgery under general anaesthesia on an outpatient basis or hospitalised at our institution between 1 January and 31 May 2019. METHODS: Descriptive, cross-sectional, retrospective study; 28 patients with low perioperative risk who underwent general anaesthesia were selected. Changes in heart rate and blood pressure were analysed during the first 6 minutes after the administration of hyoscine butylbromide. The data obtained was recorded in a Microsoft Excel database and analysed using the Excel analysis tool and IBM SPSS. RESULTS: The average dose of 0.15mg/kg of hyoscine butylbromide achieved an increase in heart rate and mean arterial pressure in 96% and 92.8%, respectively, in the first 6 minutes after the administration. Significant changes in heart rate and blood pressure were obtained during the first 6 minutes at doses between 0.05mg/kg and 0.15mg/kg. CONCLUSION: Hyoscine butylbromide generates positive effects on the heart rate and blood pressure of patients under general anaesthesia, representing a possible alternative in the management of intraoperative bradycardia.

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BACKGROUND: Hyoscine butylbromide (HBB) has been available for use as an antispasmodic since 1951 and is indicated for the treatment of abdominal pain associated with cramps. A previous review in 2007 summarized the evidence on the mode of action of HBB in vitro and in vivo in both animal and human studies. However, since then, novel publications have appeared within the literature and also our knowledge of what represents normal motility in humans has evolved. PURPOSE: This review is the result of the collaboration between a basic scientist and clinicians with the aim of providing an updated overview of the mechanisms of action of HBB and its clinical efficacy to guide not only use in clinical practice, but also future research.

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Hyoscine butylbromide-induced pyschosis, though rare, should be considered in a child presenting with deteriorating cognitive functions and psychotic features acutely as evident in our case of a 9-year-old child taking hyoscine for her non-specific abdominal pain.

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This paper reports a systematic review and meta-analysis of the effectiveness of hyoscine-N-butylbromide (HBB) administration in hysterosalpingography (HSG). Four electronic databases were searched for randomised controlled trials (RCTs) that compared HBB versus placebo or no intervention in infertile women undergoing HSG. Pain during and after HSG and different adverse events including nausea, vomiting, and dizziness were evaluated. Three RCTs with 335 patients were included. The analysis showed HBB was significantly effective in reducing pain during and after HSG (MD = -0.76 mm, 95% CI [-1.35, -0.17], p = 0.01) and (MD = -0.81 mm, 95% CI [-1.07, -0.56], p < 0.001), respectively. There were no significant differences in adverse events between HBB and control groups. The methodological evidence quality was high as evaluated by GRADEpro. In conclusion, this review provides good evidence that prior administration of HBB is effective in reducing induced pain during and after HSG with tolerable side effects.

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RESEARCH QUESTION: What is the effect of adding an anti-spasmodic drug to an existing ultrasound-guided manual vacuum aspiration (USG-MVA) protocol to alleviate immediate post-procedure abdominal cramping pain in women treated for early pregnancy loss? DESIGN: Double-blind, placebo-controlled, randomized controlled trial conducted between February 2018 and January 2020. Participants were assigned to receive a 1-ml intravenous injection containing 20-mg hyoscine butylbromide (HBB) (n=55) or saline (n =56) as a control immediately before USG-MVA. Primary outcome was reduced abdominal pain after adding a 20-mg dose of HBB to the current pain control regimen. Secondary outcomes were vaginal pain, complications and side-effects, women's pre- and post-procedure psychological state, physiological stress (saliva alpha-amylase) and procedure pain control satisfaction. Two-way mixed ANOVA was used to evaluate the main effects and interactions. RESULTS: VAS abdominal pain scores in the HBB group were 16% lower immediately after and 21% lower 2 h after surgery (not statistically significant). Two-way ANOVA indicated that time (F[1108] = 83.41, P < 0.001) was the only significant main effect for reduced abdominal pain after the procedure and vaginal pain score (F[1108] = 180.1, P < 0.0001) but not drug received. No adverse events were reported. No significant difference was found for psychological state, physiological stress and procedure pain control satisfaction between the two groups. CONCLUSIONS: Anti-spasmodic drugs can help to reduce abdominal cramping pain associated with USG-MVA; HBB produced an insignificant decrease in abdominal pain score. Further studies with longer acting or larger doses of anti-spasmodic drugs are warranted.

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OBJECTIVE: To assess the safety and efficacy of hyoscine butyl bromide (HBB) in primipara with prolonged 1st stage of labor. MATERIALS AND METHODS: A double-blinded randomized controlled trial included 100 primiparas diagnosed with prolonged labor. They were randomly divided two equal groups. Group I received 40 mg HBB intravenously. Group II received 2 ml of normal saline. The primary outcome was the duration of the 1st stage of labor. Secondary outcomes included success of vaginal delivery, rate of cervical dilation, duration of 2nd and 3rd stages of labor, causes of CS, neonatal outcome and drug side effects. RESULTS: The duration of the 1st stage was 322.3 ± 89.8 min in women who received HBB compared with 451.3 ± 198.3 min in the control women (P < 0.001). The rate of cervical dilation was increased from 0.4 ± 0.2 to 1.5 ± 0.6 in women who received HBB compared with its increase from 0.4 ± 0.1 to 0.9 ± 0.2 in other women (P < 0.001). The rate of CS were significantly higher in control women when compared to those received HBB (34 vs. 20%, P < 0.001). The commonest indication for the operation was arrest of cervical dilatation (28 and 16%, respectively). CONCLUSION: HBB is associated with shortening of the 1st stage, lowered rate of CS without any side effects. GOV ID: NCT03430362 date of registration 6 February 2018. Synopsis Hyoscine butyl bromide is associated with shortening of the 1st stage, lowered rate of CS in primiparas with prolonged labor.

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PURPOSE: Bowel motion is a significant source of artifacts in mouse abdominal MRI. Fasting and administration of hyoscine butylbromide (BUSC) have been proposed for bowel motion reduction but with inconsistent results and limited efficacy assessments. Here, we evaluate these regimes for mouse abdominal MRI at high field. METHODS: Thirty-two adult C57BL/6J mice were imaged on a 9.4T scanner with a FLASH sequence, acquired over 90 min with ~19 s temporal resolution. During MRI acquisition, 8 mice were injected with a low-dose and 8 mice with a high-dose bolus of BUSC (0.5 and 5 mg/kg, respectively). Eight mice were food deprived for 4.5-6.5 hours before MRI and another group of eight mice was injected with saline during MRI acquisition. Two expert readers reviewed the images and classified bowel motion, and quantitative voxel-wise analyses were performed for identification of moving regions. After defining the most effective protocol, high-resolution T2 -weighted and diffusion-weighted images were acquired from 4 mice. RESULTS: High-dose BUSC was the most effective protocol for bowel motion reduction, for up to 45 min. Fasting and saline protocols were not effective in suppressing bowel motion. High-resolution abdominal MRI clearly demonstrated improved image quality and ADC quantification with the high-dose BUSC protocol. CONCLUSION: Our data show that BUSC administration is advantageous for abdominal MRI in the mouse. Specifically, it endows significant bowel motion reduction, with relatively short onset timings after injection (~8.5 min) and relatively long duration of the effect (~45 min). These features improve the quality of high-resolution images of the mouse abdomen.

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INTRODUCTION: Prolonged labor increases the risk of maternal and fetal complications. The active management of labor has been proven effective in lowering neonatal and maternal morbidity by shortening the duration of labor. Several pharmaceutical and non-pharmaceutical approaches are currently being used in the active management of labor. Hyoscine Butyl-bromide (HBB) is an antispasmodic and anticholinergic drug that acts as a cervical spasmolytic agent. It has been widely used in everyday practice for shortening the active phase of labor. Nonetheless, only a few trials have been conducted on the topic. OBJECTIVE: This review aimed to evaluate whether HBB is effective in decreasing the mean duration of the active phase of labor. STUDY DESIGN: An electronic search was conducted on Medline (through PubMed), Scopus, ClinicalTrials.gov, EMBASE, PROSPERO, and Cochrane Library from the beginning of all databases to December 2019. Results were limited to randomized trials. Restriction for English language was applied. Inclusion criteria were: randomized clinical trials regarding primiparae or multiparae women with a singleton vertex pregnancy at term who were randomized to HBB versus placebo or other drugs. Primary outcome evaluated was the mean reduction of the active phase of labor. DATA COLLECTION AND ANALYSIS: Eight randomized clinical trials, including 1159 pregnant women, were analyzed. Significant heterogeneity (I2 = 99 %) between studies was noted for the primary outcome. The active phase of labor duration was significantly reduced in the treatment arm compared to controls [mean difference (MD) -83.93 min (95 % confidence interval (CI) -163.61, -4.25)]. Achieved reduction in primiparae women was -55.09 min [95 % CI -68.83, -41.35; I2 = 37 %]. CONCLUSION: HBB is an effective treatment to shorten the duration of the active phase of labor in primiparae and multiparae women.

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BACKGROUND: Cervical dilation is indicated prior to performing various gynecological procedures. However, gynecologists are at times confronted with a stenotic or tight cervix, resistant to dilation. This can be problematic particularly when cervical ripening has not been attempted hours before the start of the procedure. OBJECTIVE: The objective of this study is to investigate the efficacy of administration of hyoscine butylbromide for cervical dilation for immediate dilation of the tight or stenotic cervix. MATERIALS AND METHODS: In this clinical trial study, a population of 40 women, aged 20-70 yr with stenotic cervix, evidenced by resistance to pass dilator #2 through their cervical canal were compared. Cervical patency was assessed 10 min following intra-cervical canal instillation of hyoscine butylbromide. RESULTS: Cervical width of 57.5% of patients became wider, as evidenced by passage of the number 4 Hegar dilator through the cervical canal without resistance. Independent T-tests did not reveal any statistically significant difference between the two groups based on their age. Fisher Exact test revealed a statistically significant difference between the two groups based on the prior route of delivery, with a more statistically significant response in patients who had vaginal deliveries. CONCLUSION: Intra-cervical canal instillation of hyoscine butylbromide is effective in immediate dilation of the tight or stenotic cervix during intra-uterine procedures.

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The results of research on selected drugs used in palliative care are presented, including fentanyl, tramadol, metoclopramide, hyoscine butylbromide, midazolam, haloperidol, levomepromazine and clonazepam. Interpretation of their ESI mass spectra obtained by the use of a triple quadrupole linear ion trap mass spectrometer is given. As a result, fragmentation pathways described in the literature are complemented and presented with more details. On their basis, transitions for quantitative analysis are selected and chromatographic conditions for the determination of the palliative care drugs are proposed as well. These results enable future studies on palliative care drugs in elderly patients including both their quantitation in body fluids and easier identification of their metabolites.

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CONTEXT: Death rattle (DR) is a dramatic sign in the dying patient. Existing studies with anticholinergic agents are controversial, as this class of drugs has been commonly administered without considering the rationale of the mechanism of action. A meaningful use of these drugs may provide a better outcome. OBJECTIVES: The aim of this study was to assess the efficacy of hyoscine butylbromide (HB), given prophylactically in comparison with HB administered once DR occurs. METHODS: Dying patients having a score of ≥3 in the Richmond Agitation-Sedation Scale-palliative version were included in the study. HB (60 mg/day) was given when DR occurred (Group 1) or as pre-emptive treatment (Group 2). The onset of DR (death rattle free time) and intensity of DR were recorded at intervals until death. RESULTS: Eighty-one and 51 patients were randomized to Group 1 and 2, respectively. Patients in Group 2 survived longer than those in Group 1 (P < 0.05). DR occurred in 49 (60.5%) and three patients (5.9%) in Group 1 and 2, respectively (P = 0.001). A significant difference in the number of patients reporting DR was found at intervals examined (30 minutes, one hour, and then every six hours until death [P = 0.001]). In Group 1 and 2, DR free time was 20.4 (20.5) and 27.3 hours (25.2), respectively (P = 0.001). In Group 1, the treatment was considered effective in 10 patients (20.4%) only, after a mean of 14.4 hours (SD 8.57). CONCLUSION: The prophylactic use of HB is an efficient method to prevent DR, whereas the late administration produces a limited response, confirming data from traditional studies performed with anticholinergics. This could be considered a new paradigm to manage a difficult and dramatic sign, such as DR.

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OBJECTIVE: To assess the effect of hyoscine butylbromide (HBB) on duration of the first stage of labor in primigravdae. METHODS: A case-control study conducted on 120 primigravida at term admitted in active labor were divided into three equal groups. A single dose of the drug (placebo or HBB 20 mg or HBB 40 mg) was injected intravenously slowly to groups A, B, and C. The duration of the first stage was calculated from the time of cervical dilatation of three to four centimeters in active labor until a fully dilated cervix was observed. RESULTS: The duration of first stage was significantly shorter in women receiving 20 and 40 mg of HBB when controlled to control women (187.73 ± 20.92, 186.41 ± 19.40 versus 231.39 ± 33.14 min). There was no significant difference between the three study groups regarding duration of the second stage (36.76 ± 9.98, 35.72 ± 9.97 and 37.55 ± 10.57, respectively, p > .05), number of cases delivered by cesarean section (12.5%, 12.5%, and 15%, respectively, p > .05) and Apgar score of the neonates (p > .05). There was no significant difference between the three study groups regarding occurrence of side effects named dry mouth (7.5%, 12.5%, and 5%, p > .05), flushing (2.5%, 5% and 0%, p > .05), tachycardia (2.5%, 2.5%, and 2.5%, p > .05), or urinary retention (2.5%, 0%, and 0%, p > .05). CONCLUSION: Intravenous injection of HBB decreases the duration of active phase of labor in primigravidae with no side effects.

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OBJECTIVES: To prospectively evaluate the effect of hyoscine butylbromide (HBB) on visualisation of anatomical details and motion-related artefacts in mp-MRI of the prostate at 3.0 Tesla. METHODS: One hundred and three consecutive patients (65 ± 10 years) were included in this trial, powered to demonstrate an improvement of image quality after HBB administration, assessed on a 5-point scale by two blinded readers. All patients received high-spatial resolution axial T2-weighted TSE sequences at 3.0 T without spasmolytic agent, repeated after application of 40 mg HBB and followed by routine mp-MRI. Secondary endpoints were (1) susceptibility to side effects, (2) dependence of spasmolytic effect on patients´ weight, and (3) prostate volume. RESULTS: In 68% of patients, HBB significantly improved the anatomic score (mean 3.4 ± 0.9 before and 4.4 ± 0.7 after HBB for both readers, p = <0.001). In 67%, HBB significantly enhanced the artefact score (mean 3.2 ± 1 before and 4.2 ± 0.8 after HBB for reader 1, p = <0.001; 3.2 ± 1 and 4.1 ± 0.8 for reader 2, p = <0.001). Subgroup analysis revealed no statistically significant difference between patients with different bodyweight or prostate volume. Inter-reader agreement was excellent (k = 0.95-0.98). CONCLUSIONS: Hyoscine butylbromide significantly improves image quality and reduces motion-related artefacts in mp-MRI of the prostate independent of bodyweight or prostate volume. No side effects were reported. KEY POINTS: • Hyoscine butylbromide (HBB) improved image quality in over 2/3 of patients. • Severe artefacts were reduced after HBB in more than 20%. • The number of non-diagnostic MRI was reduced to <1% after HBB. • HBB effect was independent of bodyweight and prostate volume. • No side effects of HBB were reported in this study population.

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OBJECTIVE: Hyoscine butyl bromide (HBB) is known for its antispasmodic action and has been in use for over five decades, there is however no consensus on its effectiveness in the labor process. The aim of this study was to determine the effect of HBB on the duration of the active phase of labor. MATERIALS AND METHODS: A randomized double-blind placebo-controlled clinical trial involving 160 parturient who received either intravenous Hyoscine butyl-bromide (20 mg in 1 ml; n = 80) or intravenous normal saline (1 ml, n = 80). The mean duration of active phase of labor was compared between the two groups. RESULTS: The observed mean duration of the active phase of labor was significantly shorter (P = 0.001) in the Hyoscine butyl-bromide group (365.11 ± 37.32 min, range = 280-490) than in the Placebo group (388.46 ± 51.65 min, range = 280-525). There was no significant difference between the two groups in the mean duration of the second and third stages of labor (20.46 ± 10.46 vs. 23.38 ± 18.95 min, P = 0.43 and 8.96 ± 4.34 vs. 9.23 ± 5.92 min, P = 0.75, respectively). The mean 1-min APGAR scores were also comparable (8.08 ± 1.54 vs. 7.64 ± 1.60, P = 0.08). The mean postpartum blood loss was significantly less in the Hyoscine butyl-bromide group (303 ± 96.52 vs. 368 ± 264.19 ml, P = 0.04). CONCLUSION: Hyoscine butyl-bromide was effective in shortening the duration of the active phase of labor. It was also associated with significantly less postpartum blood loss.

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Diperiodatoargentate(III) (DPA)/silver(III) complex, [Ag(HIO6)2]5-, in sulfuric acid medium has been used to determine hyoscine butylbromide (HBB) by flow injection (FI) coupled with chemiluminescence (CL) detector. A linear standard curve between the CL intensity and concentration range from 0.005 to 20 mg L-1 was obtained. The determination coefficient (R2), limit of detection (3s × blank), relative standard deviation (RSD) for 0.5 mg L-1 HBB and analytical throughput were 0.9992 (n = 8), 5 × 10-4 mg L-1, 1.5% (n = 10) and 160 injections h-1, respectively. The developed method was applied for the determination of HBB in pharmaceutical formulations with recoveries from 92 ± 4 to 108 ± 3%. For comparison, a spectrophotometric method was used and the results obtained by both methods were in good agreement at a 95% confidence level. The effect of key chemical and physical variables (reagent concentration, flow rate, sample volume, PMT voltage) and interfering species (pharmaceutical excipients and inorganic ions) on the determination of HBB was examined. The possible CL mechanism of HBB on silver(III) complex in sulfuric acid medium was also discussed in brief.

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