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.

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: 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.

UNASSIGNED: Kidney damage can result from various factors, leading to structural and functional changes in the kidney. Acute kidney injury (AKI) refers to a sudden decline in kidney function, while chronic kidney disease involves a gradual deterioration lasting more than 3 months. Mechanisms of renal injury include impaired microcirculation, inflammation, and oxidative stress. Cysteinyl-leukotrienes (CysLTs) are inflammatory substances contributing to tissue damage. Montelukast, a leukotriene receptor antagonist, has shown potential renoprotective effects in experimental models of kidney injury.
UNASSIGNED: The authors conducted a scoping review using PubMed, Scopus, and Web of Science databases to identify relevant studies investigating the impact of montelukast on renal diseases. Articles published until 2022 were included and evaluated for quality. Data extraction and analysis were performed based on predetermined inclusion criteria.
UNASSIGNED: The scoping review included 30 studies from 8 countries. Montelukast demonstrated therapeutic effects in various experimental models of nephrotoxicity and AKI induced by agents such as cisplatin, lipopolysaccharide, diclofenac, amikacin, Escherichia coli, cyclosporine, methotrexate, cobalt-60 gamma radiation, doxorubicin, and cadmium. Studies involving human subjects with nephrotic syndrome, pyelonephritis, and other renal diseases also reported positive outcomes with montelukast treatment. Montelukast exhibited anti-inflammatory, anti-apoptotic, antioxidant, and neutrophil-inhibiting properties, leading to improved kidney function and histopathological changes.
UNASSIGNED: Montelukast shows promise as a renoprotective medication, particularly in early-stage kidney injury. Its ability to mitigate inflammation, oxidative stress, and neutrophil infiltration contributes to its therapeutic effects. Further research is needed to explore the clinical applications and mechanisms underlying the renoprotective action of montelukast.

The association between the use of certain medications (including sulfonamides, hydralazine, and procainamide) and the occurrence of drug-induced lupus or hepatitis is well established. More recently, cases of immune-related adverse events ranging from inflammatory polyarthritis to necrotizing myositis in patients taking checkpoint inhibitors have been reported. However, data linking drugs to systemic vasculitis are scarce and at times debatable. Propylthiouracil, hydralazine, and minocycline have been associated with rare cases of ANCA-associated syndromes, including life-threatening pulmonary-renal syndromes and systemic polyarteritis nodosa-like diseases. Eosinophilic granulomatosis with polyangiitis (EGPA) has been reported in patients taking leukotriene inhibitors. Since the link between the use of leukotriene inhibitors and occurrence of EGPA remains highly controversial, we performed a literature review for cases of EGPA in patients taking montelukast without prior history of oral corticosteroid use. We found 24 cases, along with our own two cases described, making 26 cases in total. The mean age was 43 and a majority (18/26) were female. In majority of cases EGPA-like disease never relapsed after they were taken off leukotriene inhibitors suggesting a clear causal relationship between the use of these drugs and occurrence of eosinophil-rich systemic EGPA.

BACKGROUND: Leukotrienes play a significant role in the pathogenesis of adenoid hypertrophy (A.H.). Therefore, we aimed to analyse the role of montelukast, a leukotriene receptor antagonist, alone or in combination with mometasone, a potent local intranasal steroid, for the treatment of A.H.
METHODS: Participants were children with A.H. were treated with montelukast alone or montelukast and mometasone furoate. The main outcome measures were effect of montelukast on clinical symptoms of A.H. A literature review was conducted using online search engines, Cochrane Library, PubMed, Web of Science and Scopus, for randomized clinical trials assessing children with A.H. treated with montelukast alone or montelukast and mometasone furoate. Seven randomized clinical trials (RCTs) were included with 742 children.
RESULTS: Our study reveals that montelukast alone or in combination with intranasal mometasone furoate significantly improves clinical symptoms of adenoid hypertrophy such as snoring, sleeping disturbance, mouth breathing and A/N ratio. Montelukast was superior to placebo in decreasing snoring (SMD = -1.00, 95% CI [-1.52, -0.49]), sleep discomfort (SMD = -1.26, 95% CI [-1.60, -0.93]), A/N ratio (MD = -0.11, 95% CI [-0.14, -0.09]) and mouth breathing (SMD = -1.36, 95% CI [-1.70, -1.02]). No difference was detected between montelukast and mometasone versus mometasone alone in snoring (SMD = -0.21, 95%CI [-0.69, 0.27]); however, the combination group was superior to the mometasone alone in mouth breathing (SMD = -0.46, 95% CI [-0.73, -0.19]).
CONCLUSIONS: The limitation of studies included a small sample size, with an overall low to medium quality. Thus, further larger, higher-quality RCTs are recommended to provide more substantial evidence.

Lung and hematopoietic stem cell transplantation are therapeutic modalities in chronic pulmonary and hematological diseases, respectively. One of the complications in these patients is the development of bronchiolitis obliterans syndrome (BOS). The efficacy and safety of available treatment strategies in BOS remain a challenge. A few mechanisms have been recognized for BOS in lung transplant and graft-versus-host disease (GVHD) patients involving the TH-1 and TH-2 cells, NF-kappa B, TGF-b, several cytokines and chemokines, and cysteinyl leukotrienes (CysLT). Montelukast is a highly selective CysLT receptor antagonist that has been demonstrated to exert anti-inflammatory and anti-fibrotic effects in abundant experiments. One area of interest for the use of montelukast is lung transplants or GVHD-associated BOS. Herein, we briefly review data regarding the mechanisms involved in BOS development and montelukast administration as a treatment modality for BOS, and finally, the possible relationship between CysLTs antagonism and BOS improvement will be discussed.
A review of the therapeutic potential and possible mechanism of Montelukast in the treatment of bronchiolitis obliterans syndrome following lung and hematopoietic stem cell transplantationLung and bone marrow transplantation are therapeutic modalities in chronic diseases of the lungs and the blood, respectively. One of the complications in these patients is the development of Bronchiolitis obliterans syndrome (BOS). The efficacy and safety of available treatment strategies in BOS remain a challenge. A few mechanisms for BOS in lung transplant and graft-versus-host disease (GVHD) patients involving many immune components have been recognized. Cysteinyl leukotrienes are products of plasma membrane phospholipids that increase smooth muscle contraction, microvascular permeability, and airway mucus secretion. Montelukast is a highly selective cysteinyl leukotriene receptor blocker demonstrated to exert anti-inflammatory and anti-fibrotic effects. One area of interest for the use of montelukast is in lung transplant- or GVHD-associated BOS. In this article, we briefly review data regarding the mechanisms involved in BOS development and montelukast administration as a treatment modality for BOS. Finally, the possible relationship between cysteinyl leukotriene inhibition and BOS improvement will be discussed.

Background: Loratadine and montelukast are clinical first-line drugs in the treatment of allergic rhinitis (AR). However, there is no clear evidence of the efficacy of loratadine combined with montelukast in the treatment of AR. This study aimed to evaluate the efficacy and safety of the loratadine-montelukast combination on AR. Methods: In this meta-analysis, searches were conducted on PubMed, Embase, the Cochrane Central Register of Controlled Trials, Web of Science, and China National Knowledge Infrastructure (CNKI). The search terms included loratadine, montelukast, allergic rhinitis, and clinical trials. Meta-analyses were conducted using Rev Man 5.3 and Stata 15 statistical software. Results: A total of 23 studies with 4,902 participants were enrolled. For the primary outcome, pooled results showed that loratadine-montelukast can significantly reduce total nasal symptom scores (TNSS), when compared with loratadine (SMD, -1.00; 95% CI, -1.35 to -0.65, p < 0.00001), montelukast (SMD, -0.46; 95% CI, -0.68 to -0.25, p < 0.0001), or placebo (SMD, -0.93; 95% CI, -1.37 to -0.49, p < 0.00001). For secondary outcomes, pooled results showed that compared with loratadine, loratadine-montelukast can significantly improve nasal congestion, nasal itching, nasal sneezing, nasal rhinorrhea, and rhinoconjunctivitis quality of life questionnaires (RQLQ). Compared with montelukast, loratadine-montelukast can significantly improve nasal itching, and nasal sneezing. Compared with placebo, loratadine-montelukast can significantly improve nasal congestion, and RQLQ. Conclusion: Loratadine-montelukast combination is superior to loratadine monotherapy, montelukast monotherapy, or placebo in improving AR symptoms. Therefore, loratadine-montelukast combination can be an option for patients with moderate-severe AR or poorly response to monotherapy. Systematic review registration number: clinicaltrials.gov, identifier CRD42023397519.

BACKGROUND: Montelukast is a highly selective and specific cysteinyl leukotriene receptor antagonist used in the treatment of asthma. Whether montelukast as adjuvant therapy can significantly and safely treat adults with cough variant asthma (CVA) remains inconclusive.
OBJECTIVE: This meta-analysis systematically evaluated the efficacy and safety of montelukast as an adjuvant treatment for adults with CVA.
METHODS: Randomized controlled trials (RCTs) on montelukast combined with inhaled corticosteroids (ICS) and long-acting β2 agonists (LABAs) to treat CVA in adults, from inception to March 6, 2023, were retrieved from the CNKI, Wanfang, VIP, CBM, PubMed, Embase, Cochrane Library, and Web of Science databases and Clinical Trials website. Review Manager (version 5.4) and Stata (version 15.0) were used to conduct the meta-analysis.
RESULTS: A total of 15 RCTs were ultimately included in the meta-analysis. It was established that montelukast as adjuvant therapy raised the total effective rate (RR = 1.20, 95% confidence interval [CI] [1.13, 1.27], P < 0.01) and improved the FEV1% (SMD = 0.91, 95% CI [0.40, 1.41], P < 0.01), PEF% (SMD = 0.63, 95% CI [0.38, 0.88], P < 0.01), FEV1 (SMD = 1.15, 95% CI [0.53, 1.77], P < 0.01), PEF (SMD = 0.64, 95% CI [0.42, 0.86], P < 0.01), and FEV1/FVC% (SMD = 0.76, 95% CI [0.51, 1.01], P < 0.01) and reduced the recurrence rate (RR = 0.28, 95% CI [0.15, 0.53], P < 0.01). The incidence of adverse reactions was higher in the montelukast auxiliary group compared to the control group but with no statistical difference (RR = 1.32, 95% CI [0.89, 1.96], P = 0.17).
CONCLUSIONS: Existing evidence indicated that the use of montelukast as an adjuvant therapy had therapeutic efficacy superior to ICS + LABA alone for the treatment of adult patients with CVA. However, further research is needed, especially a combination of high-quality long-term prospective studies and carefully designed RCTs.

Coronavirus disease 2019 (COVID-19) is an emerging worldwide issue, that has affected a large number of people around the world. So far, many studies have aimed to develop a therapeutic approach against COVID-19. Montelukast (MK) is a safe asthma controller drug, which is considered as a potential antiviral drug for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). This review has a systematic approach to investigate the reports on the use of MK as a part of treatment or a prophylactic agent in COVID-19. The search was conducted in PubMed, Web of Science, and Scopus databases and yielded 35 studies containing the influence of MK on SARS-CoV-2. Ultimately, MK appears to be worth being used as an adjuvant therapeutic and prophylactic drug against SARS-CoV-2. Nevertheless, more clinical trials are required to accurately investigate its effectiveness.