This systematic review and meta-analysis evaluated the safety of montelukast in treating asthma during pregnancy, focusing on maternal and fetal outcomes such as congenital anomalies (CA), preterm delivery, low birthweight, spontaneous abortion, gestational diabetes mellitus, and preeclampsia. A comprehensive literature search was conducted in Google Scholar, PubMed, and the Cochrane Library databases from inception until April 30, 2024. The eligible studies assessed the safety of montelukast for asthma treatment during pregnancy. The review suggests that montelukast use during pregnancy may not significantly increase the risk of major CA. The pooled results yielded risk ratio (RR) for CA was 1.13 [95% CI (0.74, 1.73), p = 0.56, I2 = 0%]. Montelukast may be associated with preterm delivery and a low birthweight odds ratio (OR) of 1.82 [95% CI (1.35, 2.45), p < 0.001, I2 = 0%]. No significant risks were found concerning neurodevelopmental outcomes. The associations with spontaneous abortion were inconclusive [OR = 1.03, 95% CI (0.72, 1.5), p = 0.86, I2 = 73%], highlighting the need for further research. This comprehensive review underscores the importance of further investigating the safety profile of montelukast during pregnancy. While the overall findings indicate a relatively favorable safety profile, especially regarding major CA, careful consideration is needed for the potential risks of preterm delivery and low birthweight.

This study investigates the pharmacokinetics (PK) of montelukast (MTK), a cysteinyl leukotriene receptor antagonist increasingly being considered in veterinary medicine. In dogs, MTK has found indications mainly for treating atopic dermatitis as an off-label use. Six male Labrador dogs underwent a single oral administration of MTK (40mg/dog) in both fasted and fed conditions according to an open, single-dose, two-treatment, two-phase, cross-over design, with a washout period of one week. Blood was withdrawn to heparinized tubes at 0, 0.25, 0.5, 0.75, 1, 1.5, 2, 4, 6, 8, 10, and 24hr. MTK plasma concentrations were quantified using a validated HPLC method, and the data were analysed using PKanalixTM software with a non-compartmental approach. Concentrations remained quantifiable at 24hr after administration, under both conditions. No significant differences were observed in the PK parameters between the fasted and fed states. MTK was relatively eliminated slowly, with t1/2 values of 8.10 and 7.68hr after fasted and fed states, respectively. The attainment of maximum concentration (Cmax) occurred at a Tmax of 4hr, with mean values of 1.98μg/mL and 2.80μg/mL under fasted and fed conditions, respectively. Given the unknown therapeutic range of MTK in dogs and the absence of controlled studies proving its efficacy in this species, further dosing adjustments and refinements should be considered based on both the current PK data and the need to establish an effective therapeutic range, if present. Future research should focus on efficacy studies, multiple-dose investigations, and pharmacodynamic assessments to evaluate the suitability of MTK use in dogs.

The purpose of this study was to enhance the stability of montelukast and levocetirizine for the development of a fixed-dose combination (FDC) monolayer tablet. To evaluate the compatibility of montelukast and levocetirizine, a mixture of the two drugs was prepared, and changes in the appearance characteristics and impurity content were observed in a dry oven at 60 °C. Excipients that contributed minimally to impurity increases were selected to minimize drug interactions. Mannitol, microcrystalline cellulose, croscarmellose sodium, hypromellose, and sodium citrate were chosen as excipients, and montelukast-levocetirizine FDC monolayer tablets were prepared by wet granulating the two drugs separately. A separate granulation of montelukast and levocetirizine, along with the addition of sodium citrate as a pH stabilizer, minimized the changes in tablet appearance and impurity levels. The prepared tablets demonstrated release profiles equivalent to those of commercial products in comparative dissolution tests. Subsequent stability testing at 40 ± 2 °C and 75 ± 5% RH for 6 months confirmed that the drug content, dissolution rate, and impurity content met the specified acceptance criteria. In conclusion, the montelukast-levocetirizine FDC monolayer tablet developed in this study offers a potential alternative to commercial products.

Cholangiocarcinoma (CCA) is a cancer with a poor prognosis due to difficulties in diagnosis and limited treatment options, highlighting the urgent need for new targeted therapies. In a clinical setting, we found that leukotriene levels in bile were higher than in serum. Immunohistochemical analysis of surgically resected samples also revealed that CysLT receptor 1 (CysLTR1) was more highly expressed in CCA than in normal bile duct tissue, prompting us to investigate leukotriene as a potential therapeutic target in CCA. In vitro studies using CCA cell lines expressing CysLTR1 showed that leukotriene D4, a major ligand of CysLTR1, promoted cell proliferation, with increased phosphorylation of AKT and extracellular signal-regulated kinase 1/2 (ERK1/2). Additionally, treatment with two clinically available anti-allergic drugs-zileuton, an inhibitor of CysLT formation, and montelukast, a CysLTR1 inhibitor-had inhibitory effects on cell proliferation and migratory capacity, accompanied by the reduced phosphorylation of AKT and ERK1/2. Furthermore, the simultaneous administration of both drugs synergistically enhanced the inhibitory effect on cell proliferation. Our study suggests that use of these drugs may represent a novel approach to treat CCA through drug repositioning.

UNASSIGNED: Placental insufficiency is a serious complication that affects pregnancy and fetal growth. Cyclophosphamide (CYC) is considered one of the chemotherapeutic agents. Unfortunately, CYC not only affects tumor cells but also affects healthy cells causing multiple injuries including the placenta. The present study aimed to evaluate the effect of cysteinyl leukotriene receptor antagonist; montelukast (MK), on CYC-induced placental injury in rats.
METHODS: Forty-eight female Wister rats were randomly divided into 8 experimental groups. Group 1: control pregnant group; Group 2: MK 5 mg-treated pregnant rats; Group 3: MK 10 mg-treated pregnant rats; Group 4: MK 20 mg-treated pregnant rats; Group 5: pregnant rats received CYC (20 mg/kg, i.p); Group 6: pregnant rats received MK 5 mg and CYC; Group 7: pregnant rats received MK 10 mg and CYC; Group 8: pregnant rats received MK 20 mg and CYC. Placental malondialdehyde (MDA), reduced glutathione (GSH), total antioxidant capacity (TAC), placental growth factor (PlGF), and Nod-like receptor p3 (NLRP3) inflammasome were measured. Histological changes, interleukin-1β (IL-1β), and cleaved caspase-3 immuno-expressions were also evaluated.
RESULTS: CYC showed a significant decrease in placental GSH, TAC, and PlGF with a significant increase in placental MDA, NLRP3, and immuno-expression of IL-1β and caspase-3. MK showed significant improvement in all oxidative stress (MDA, GSH and TAC), inflammatory (NLRP3 and IL-1β), and apoptotic (caspase-3) parameters.
CONCLUSIONS: According to the findings, MK was proved to have a possible protective role in CYC-induced placental injury via modulation of NLRP3/IL-1β signaling pathway with anti-oxidant, anti-inflammatory, and anti-apoptotic effects.

Morbihan\'s disease is a rare condition characterized by chronic facial edema. While its exact cause is unknown, it is thought to involve local cutaneous vascularization and lymphatic drainage imbalance. Traditional treatment options are often ineffective, and no established efficient treatment exists. We present a case study of a 17-year-old male with Morbihan\'s syndrome who showed resistance to traditional treatments but responded well to a combination of cromolyn sodium nasal spray and oral montelukast after histopathology revealed hyperplasia of plasma cells and mast cells. This combination has not been used before for Morbihan\'s syndrome. Our review of the literature also provides insight for clinicians seeking to manage this condition.

BACKGROUND: Dengue fever continues to pose significant health challenges globally, with recent outbreaks in Bihar, India, prompting a search for effective therapeutic interventions. This study assesses the effectiveness of Montelukast, traditionally used for asthma, in mitigating the severity of dengue fever symptoms and its progression to dengue shock syndrome (DSS).
OBJECTIVE: To evaluate the impact of Montelukast on the prevalence of dengue warning signs and the incidence of DSS in adult patients.
METHODS: A prospective observational study was conducted at the Indira Gandhi Institute of Medical Sciences (IGIMS), Patna, India, from August 2022 to October 2023, enrolling 500 patients diagnosed with dengue fever. Participants were divided into two groups. About 250 were treated with Montelukast and 250 received standard care. Outcomes measured included the incidence of warning signs, DSS, length of hospital stay, and 30-day mortality.
RESULTS: The Montelukast group exhibited a 24% lower prevalence of dengue warning signs compared to the control group, with 90 out of 250 patients (36%) in the Montelukast group versus 150 out of 250 patients (60%) in the control group (p < 0.001). The incidence of DSS was significantly reduced in the Montelukast group, with 4 out of 250 patients (1.6%) compared to 21 out of 250 patients (8.4%) in the control group (odds ratio: 0.178, p < 0.001). Furthermore, Montelukast users experienced shorter hospital stays (average 4.52 days vs. 6.54 days, T-statistic: -7.59, p = 1.58×10-13) and a reduced 30-day mortality rate, with 5 out of 250 patients (2%) in the Montelukast group versus 12 out of 250 patients (5%) in the control group (p < 0.03).
CONCLUSIONS: Montelukast significantly lowers the incidence of dengue warning signs and DSS, shortens hospital stays, and decreases mortality rates among dengue patients, supporting its potential integration into existing dengue treatment protocols. This study highlights the need for further clinical trials to confirm these findings and fully understand the therapeutic mechanisms of Montelukast in dengue management.

Montelukast by inhibiting leukotriene receptors in the bladder can prevent the activation of mast cells. We investigated the effectiveness of Montelukast in reducing the symptoms of children with bladder pain syndrome (BPS). In this randomized clinical trial, children were allocated into groups of intervention (Montelukast and oxybutynin) and the control (oxybutynin). At the beginning and after 14 days, questions from mothers of children about their urinary condition were asked about the frequency of nocturnal enuresis, frequent urination, urinary incontinence, urinary urgency, and their pain severity. There was no significant difference between two groups in terms of frequency of nocturnal enuresis, frequent urination, urinary incontinence, and urinary urgency. Regarding the frequency of pain distribution, the frequency of pain-free people in the Montelukast group was higher than control group (84.4% vs 56.3%, P = .023). The results showed that adding Montelukast to oxybutynin has a significant decrease in pain in children with BPS.

BACKGROUND: The benefits and harms of adding antileukotrienes to H1 antihistamines (AHs) for the management of urticaria (hives, itch, and/or angioedema) remain unclear.
OBJECTIVE: We sought to systematically synthesize the treatment outcomes of antileukotrienes in combination with AHs versus AHs alone for acute and chronic urticaria.
METHODS: As part of updating American Academy of Allergy, Asthma & Immunology and American College of Allergy, Asthma, and Immunology Joint Task Force on Practice Parameters urticaria guidelines, we searched Medline, Embase, Central, LILACS, WPRIM, IBECS, ICTRP, CBM, CNKI, VIP, Wanfang, US Food and Drug Administration, and European Medicines Agency databases from inception to December 18, 2023, for randomized controlled trials (RCTs) evaluating antileukotrienes and AHs versus AHs alone in patients with urticaria. Paired reviewers independently screened citations, extracted data, and assessed risk of bias. Random effects models pooled effect estimates for urticaria activity, itch, wheal, sleep, quality of life, and harms. The GRADE approach informed certainty of evidence ratings. The study was registered at the Open Science Framework (osf.io/h2bfx/).
RESULTS: Thirty-four RCTs enrolled 3324 children and adults. Compared to AHs alone, the combination of a leukotriene receptor antagonist with AHs probably modestly reduces urticaria activity (mean difference, -5.04; 95% confidence interval, -6.36 to -3.71; 7-day urticaria activity score) with moderate certainty. We made similar findings for itch and wheal severity as well as quality of life. Adverse events were probably not different between groups (moderate certainty); however, no RCT reported on neuropsychiatric adverse events.
CONCLUSIONS: Among patients with urticaria, adding leukotriene receptor antagonists to AHs probably modestly improves urticaria activity with little to no increase in overall adverse events. The added risk of neuropsychiatric adverse events in this population with leukotriene receptor antagonists is small and uncertain.

BACKGROUND: Capsular contracture (CC) remains a very common complication and the main cause of reoperation following a mammary implant surgery. Leukotrienes play an important role in the inflammatory cascade linked to the development of the periprosthetic capsule. The aim of this paper is to evaluate the incidence of recurrence of capsular contracture in female patients who underwent a secondary mammary augmentation due to this etiology, with and without treatment with leukotriene inhibitors during postoperative care.
METHODS: Sixty-four women submitted to a secondary mammary augmentation due to CC were evaluated retrospectively. Out of these patients, 20 (31%) were treated with Montelukast for 3 months. The remaining 44 (69%) did not receive antileukotriene. The presence of capsular contracture was measured using the Baker classification and magnetic resonance imaging a year after postoperative care. The median follow-up period was 15 months.
RESULTS: The patients receiving Montelukast (n = 20) presented a 15% CC rate (n = 1). The women that did not receive antileukotriene therapy (n = 44) presented a 16% CC rate (n = 7).
CONCLUSIONS: The results of our study show that treatment with Montelukast for 3 months after the operation is associated with lower rates of capsular contracture when compared to patients that did not receive the treatment.
METHODS: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .