Comparative safety and efficacy of a hybrid intravenous and oral diltiazem protocol for acute rate control in the emergency department.

STUDY OBJECTIVE: Intravenous diltiazem has experienced numerous supply shortages over the past few years. The purpose of this study was to compare the safety and efficacy of a traditional diltiazem intravenous bolus and continuous infusion protocol to a diltiazem intravenous bolus and oral maintenance protocol for acute rate control in the emergency department. METHODS: Patients who received intravenous diltiazem in the emergency department between January 1, 2018 and May 31, 2019 were screened. Patients were included if they received the diltiazem intravenous bolus and continuous infusion protocol (IV + infusion group) or the hybrid diltiazem intravenous bolus and oral maintenance protocol (IV + PO group). The primary outcome was the proportion of patients with rate control, without need for additional rate control agents or additional boluses during the maintenance phase. RESULTS: A total of 106 patients were matched with 53 patients in each group. For the primary outcome of rate control at four hours, 62.3% of patients in the intravenous bolus + infusion group versus 75.5% of patients in the IV bolus + PO group (p = 0.142) achieved rate control. There was no difference in rates of hypotension or bradycardia between groups. CONCLUSION: Results of this study demonstrated no difference in acute rate control when using a hybrid IV and oral diltiazem protocol, compared to a traditional IV bolus and infusion strategy. This information supports the further use of a hybrid diltiazem IV and oral protocol, which provides increased flexibility during shortages of either medication.

Diltiazem Hydrochloride Floating Matrix Tablet: Formulation and in vitro-in vivo Evaluation.

BACKGROUND: Diltiazem hydrochloride is a calcium channel-blocker with a plasma elimination half-life of 4.4 ± 1.3 h and has a narrow absorption window. So, this work aimed to prepare a gastro-retentive floating matrix tablet. METHODS: The direct compression method was used to manufacture tablets. 32 factorial design was applied for optimization, taking Hydroxypropyl Methylcellulose K100M (HPMC K 100M) and the amount of sodium bicarbonate as independent factors and cumulative percentage release at 1 h, at 6 h, and at 12 h and floating lag time as dependent variables. RESULTS: The high amount of HPMC K100M and sodium bicarbonate shows good results. The optimized preparation was evaluated for differential scanning calorimetry, in-vivo gastric retention in male albino rabbits, kinetic modeling, and stability study. An in vivo study revealed gastric retention of tablets up to 6 h in healthy male Albino rabbits. The stability study indicated no significant change in the buoyancy and release profiles of the drug. CONCLUSION: From this study, it can be concluded that the gastro-retentive diltiazem hydrochloride floating matrix tablet was successfully prepared and retained inside the rabbit stomach for up to 6 h and was stable under accelerated stability study.

Analytical QbD for the optimization of a multimode HPLC method for the investigation of hydrochlorothiazide, diltiazem and propranolol release from 3D printed formulation.

Since 3D printing technology is an emerging field in pharmaceutical technology, the present study aimed at the development of a mixed-mode liquid chromatographic method for the separation and determination of hydrochlorothiazide, diltiazem, and propranolol to investigate their in-vitro release performance from 3D printed tablets. Due to the unique properties of the mixed-mode stationary phase, the three drugs were separated in less than 8 min under isocratic elution. Method development was accomplished following the Analytical Quality by Design principles and was evaluated using risk assessment and multivariate analysis. The influences of critical method parameters on critical method attributes (were screened using a 2-level fractional factorial design and subsequently optimized through a central composite design. The method operable design region was approved by the establishment of a robust zone using Monte Carlo simulation and capability analysis. The validation of the HPLC method was performed based on the total error concept. The relative bias was varied between ─ 11.6 % and 10.5 % and the RSD values for repeatability and intermediate precision were below 4.4 % in all cases. The limits of detection (LOD) ranged between 0.17 - 0.90 µg/mL and were adequate for the specific application. The developed method was successfully applied to the analysis of the studied drugs in in-vitro drug release samples obtained from 3D-printed tablets combining the above-mentioned active pharmaceutical ingredients (APIs).

Potential interactions between medications for rate control and direct oral anticoagulants: Population-based cohort and case-crossover study.

BACKGROUND: Direct oral anticoagulants (DOACs) are commonly co-prescribed with amiodarone/diltiazem/verapamil, but whether there is a drug interaction between these drugs is unclear. OBJECTIVE: The purpose of this study was to investigate the risk of clinical outcomes associated with concomitant use of DOACs and amiodarone/diltiazem/verapamil. METHODS: We identified DOAC users in the Clinical Practice Research Datalink Aurum from January 1, 2011, to December 31, 2019. We used a cohort design to estimate hazard ratios for ischemic stroke, myocardial infarction, venous thromboembolism, intracranial bleeding, gastrointestinal bleeding, other bleeding, cardiovascular mortality, and all-cause mortality, comparing DOACs + amiodarone/diltiazem/verapamil users and DOACs + beta-blocker users. A case-crossover design comparing odds of exposure to different drug initiation patterns for all outcomes in hazard window vs referent window within an individual also was conducted. RESULTS: Of 397,459 DOAC users, we included 9075 co-prescribed amiodarone, 9612 co-prescribed diltiazem, and 2907 co-prescribed verapamil. There was no difference in risk of any outcomes between DOACs + amiodarone/diltiazem/verapamil users vs DOACs + beta-blocker users in the cohort design. However, in the case-crossover design, we observed an odds ratio (OR) of 2.09 (99% confidence interval [CI] 1.37-3.18) for all-cause mortality associated with initiation of a DOAC while taking amiodarone, which was greater than that observed for DOAC monotherapy (OR 1.30; 99% CI 1.25-1.35). Similar findings were observed for cardiovascular mortality and all-cause mortality respectively with diltiazem. CONCLUSION: Our study showed no evidence of higher bleeding or cardiovascular risk associated with co-prescribed DOACs and amiodarone, diltiazem, or verapamil. Elevated risks of cardiovascular and all-cause mortality were only observed during DOAC initiation when diltiazem/amiodarone were being taken.

Utility of native emission quenching of erythrosine B for the determination of diltiazem in different dosage forms.

This study introduces a practical and cost-effective method for tracking diltiazem (DLZ) analytically. It utilizes a fluorimetric approach that relies on the modulation of fluorescence intensity of a dye called erythrosine B. Through a one-pot experiment performed in an acidic environment, a complex is rapidly formed between DLZ and erythrosine B. By observing the decrease in erythrosine B emission, a linear calibration plot is established, enabling the detection and quantification of DLZ concentrations ranging from 40 to 850 ng/ml. The estimated limits of detection and quantitation were 10.5 and 32.1 ng/ml, respectively. The variables affecting the DLZ-dye complex system were carefully adjusted. The validity of the approach was confirmed through a thorough evaluation based on the criteria set by ICH guidelines. The accuracy and precision of the methodology were evaluated, and the standard deviation and relative standard deviation were below 2. The strategy was successfully employed to analyze DLZ in tablets and capsules, and no significant variation between the proposed and reported methods as the values of the estimated t-test and F-test at five determinations were below 2.306 and 6.338, respectively. Notably, the method adheres to the principle of green chemistry by utilizing distilled water as the dispersing medium.

Comparison of the Effectiveness and Safety of Metoprolol and Diltiazem in Atrial Fibrillation With Rapid Ventricular Rate Patients: A Systematic Review and Meta-Analysis.

This study aims to assess the association between intravenous diltiazem and metoprolol in rate control for atrial fibrillation (AF) patients with rapid ventricular rate, focusing on rate control efficacy and hemodynamic adverse events. Following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, electronic searches were conducted in Embase, PubMed, and Cochrane Central Register of Controlled Trials (CENTRAL) until February 20, 2024. The primary outcome was achieving ventricular rate control < 110/min. Secondary outcomes included new hypotension (systolic blood pressure < 90 mm Hg) and bradycardia (heart rate < 60/min). Nineteen studies (three randomized controlled trials and 16 observational studies) were included in this meta-analysis. Pooled analysis showed intravenous metoprolol resulted in a 39% lower rate control attainment compared to diltiazem (OR: 0.61; 95% CI: 0.44 to 0.84; p = 0.002). There were no significant differences in bradycardia (OR: 0.51; 95% CI: 0.22 to 1.22; p = 0.13) or hypotension risk (OR: 1.08; 95% CI: 0.72 to 1.61; p = 0.72) between the two groups. Intravenous diltiazem demonstrated superior rate control efficacy compared to metoprolol in AF patients with rapid ventricular rate. However, no significant differences were observed in safety outcomes, namely, bradycardia and hypotension.

Clinical Outcomes Associated With Diltiazem Use in Heart Failure With Reduced Ejection Fraction After Implementation of a Clinical Support System.

BACKGROUND: Despite atrial fibrillation guideline recommendations, many patients with heart failure with reduced ejection fraction (EF) continue to receive IV diltiazem for acute rate control. OBJECTIVE: Our institution recently implemented a clinical decision support system (CDSS)-based tool that recommends against the use of diltiazem in patients with an EF ≤ 40%. The objective of this study was to evaluate outcomes of adherence to the aforementioned CDSS-based tool. METHODS: This multi-hospital, retrospective study assessed patients who triggered the CDSS alert and compared those who did and did not discontinue diltiazem. The primary outcome was the occurrence of clinical deterioration. The primary endpoint was compared utilizing a Fisher's Exact Test, and a multivariate logistic regression model was developed to confirm the results of the primary analysis. RESULTS: A total of 246 patients were included in this study with 146 patients in the nonadherent group (received diltiazem) and 100 patients in the adherent group (did not receive diltiazem). There was a higher proportion of patients experiencing clinical deterioration in the alert nonadherence group (33% vs 21%, P = 0.044), including increased utilization of inotropes and vasopressors, and higher rate of transfer to ICU. CONCLUSION AND RELEVANCE: In patients with heart failure with reduced EF, diltiazem use after nonadherence to a CDSS alert resulted in an increased risk of clinical deterioration. This study highlights the need for improved provider adherence to diltiazem clinical decision support systems.

Diltiazem HCl suppresses porcine reproductive and respiratory syndrome virus infection in susceptible cells and in swine.

Porcine reproductive and respiratory syndrome virus (PRRSV) is a pathogen for swine, resulting in substantial economic losses to the swine industry. However, there has been little success in developing effective vaccines or drugs for PRRSV control. In the present study, we discovered that Diltiazem HCl, an inhibitor of L-type Ca2+ channel, effectively suppresses PRRSV replication in MARC-145, PK-15CD163 and PAM cells in dose-dependent manner. Furthermore, it demonstrates a broad-spectrum activity against both PRRSV-1 and PRRSV-2 strains. Additionally, we explored the underlying mechanisms and found that Diltiazem HCl -induced inhibition of PRRSV associated with regulation of calcium ion homeostasis in susceptible cells. Moreover, we evaluated the antiviral effects of Diltiazem HCl in PRRSV-challenged piglets, assessing rectal temperature, viremia, and gross and microscopic lung lesions. Our results indicate that Diltiazem HCl treatment alleviates PRRSV-induced rectal temperature spikes, pulmonary pathological changes, and serum viral load. In conclusion, our data suggest that Diltiazem HCl could serve as a novel therapeutic drug against PRRSV infection.

Efficacy of diltiazem 2% rectal gel in the treatment of chronic anal fissure: a retrospective observational study.

OBJECTIVE: The aim of this study is to describe the effectiveness and safety of a magistral formulation of diltiazem 2% rectal gel as a treatment for chronic anal fissure. MATERIAL AND METHODS: A retrospective observational study of all patients that began treatment with diltiazem 2% gel during 2019. The primary endpoint of the study was anal fissure healing. We also looked for differences in effectiveness between those initiating treatment and those who had been previously treated, long-term effectiveness through a 2-year follow-up and frequency of adverse effects. RESULTS: Of the 166 patients included in the study, anal fissure healed in 72.9%. We detected adverse effects in 12 patients, the most common was local irritation. After 2 years of follow-up, 88% of patients did not relapse. CONCLUSION: In this study, use of topical diltiazem 2% has been shown to be effective and safe in the treatment of anal fissure and should be considered as the first line of therapy.

OBJETIVO: El objetivo de este estudio es describir la efectividad y la seguridad de una fórmula magistral de diltiazem 2% gel rectal, como tratamiento de la fisura anal crónica. MATERIAL Y MÉTODOS: Un studio observacional retrospectivo de todos los pacientes que comenzaron a ser tratados con diltiazem 2% gel durante el año 2019. La variable principal del estudio fue la cicatrización de la fisura anal. También se buscaron diferencias de efectividad entre aquellos que iniciaban el tratamiento y los que ya habían sido tratados previamente, efectividad a largo plazo mediante un seguimiento de 2 años y frecuencia de aparición de efectos adversos. RESULTADOS: De los 166 pacientes incluidos en el estudio, el 72,9% cicatrizaron la fisura anal. No detectamos diferencias estadísticamente significativas de efectividad entre los pacientes naive y aquellos que ya habían sido tratados. Detectamos efectos adversos en 12 pacientes, siendo el más frecuente la irritación local. Tras 2 años de seguimiento, el 88% de los pacientes no presentaron ninguna recaída. CONCLUSIÓN: En este estudio, el uso de diltiazem 2% tópico ha mostrado ser efectivo y seguro en el tratamiento de la fisura anal y debería considerarse como primera línea terapéutica.

SERCA-1 conformational change exerted by the Ca2+-channel blocker diltiazem affects mammalian skeletal muscle function.

In skeletal muscle (SM), inward Ca2+-currents have no apparent role in excitation-contraction coupling (e-c coupling), however the Ca2+-channel blocker can affect twitch and tetanic muscle in mammalian SM. Experiments were conducted to study how diltiazem (DLZ) facilitates e-c coupling and inhibits contraction. 1) In complete Extensor Digitorum Longus (EDL) muscle and single intact fibres, 0.03 mM DLZ causes twitch potentiation and decreases force during tetanic activity, with increased fatigue. 2) In split open fibres isolated from EDL fibres, DLZ inhibits sarcoplasmic reticulum (SR) Ca2+-loading in a dose-dependent manner and has a potentiating effect on caffeine-induced SR Ca2+-release. 3) In isolated light SR (LSR) vesicles, SERCA1 hydrolytic activity is not affected by DLZ up to 0.2 mM. However, ATP-dependent Ca2+-uptake was inhibited in a dose-dependent manner at a concentration where e-c coupling is changed. 4) The passive Ca2+-efflux from LSR was reduced by half with 0.03 mM diltiazem, indicating that SR leaking does not account for the decreased Ca2+-uptake. 5) The denaturation profile of the SERCA Ca2+-binding domain has lower thermal stability in the presence of DLZ in a concentration-dependent manner, having no effect on the nucleotide-binding domain. We conclude that the effect of DLZ on SM is exerted by crossing the sarcolemma and interacting directly with the SERCA Ca2+-binding domain, affecting SR Ca2+-loading during relaxation, which has a consequence on SM contractility. Diltiazem effect on SM could be utilized as a tool to understand SM e-c coupling and muscle fatigue.

Sustainable asymmetric synthesis of diltiazem precursor enabled by recombinant Escherichia coli whole cells co-expressing an engineered ketoreductase and glucose dehydrogenase.

As a key synthetic intermediate of the cardiovascular drug diltiazem, methyl (2R,3S)-3-(4-methoxyphenyl) glycidate ((2R,3S)-MPGM) (1) is accessible via the ring closure of chlorohydrin (3S)-methyl 2-chloro-3-hydroxy-3-(4-methoxyphenyl)propanoate ((3S)-2). We report the efficient reduction of methyl 2-chloro-3-(4-methoxyphenyl)-3-oxo-propanoate (3) to (3S)-2 using an engineered enzyme SSCRM2 possessing 4.5-fold improved specific activity, which was obtained through the structure-guided site-saturation mutagenesis of the ketoreductase SSCR by reliving steric hindrance and undesired interactions. With the combined use of the co-expression fine-tuning strategy, a recombinant E. coli (pET28a-RBS-SSCRM2 /pACYCDuet-GDH), co-expressing SSCRM2 and glucose dehydrogenase, was constructed and optimized for protein expression. After optimizing the reaction conditions, whole-cell-catalyzed complete reduction of industrially relevant 300 g L-1 of 3 was realized, affording (3S)-2 with 99% ee and a space-time yield of 519.1 g∙L-1 ∙d-1 , representing the highest record for the biocatalytic synthesis of (3S)-2 reported to date. The E-factor of this biocatalytic synthesis was 24.5 (including water). Chiral alcohol (3S)-2 generated in this atom-economic synthesis was transformed to (2R,3S)-MPGM in 95% yield with 99% ee.

Diltiazem for clozapine-induced generalized hyperhidrosis.

Background: Clozapine can be associated with significant side effects and tolerability issues. Hyperhidrosis occurs less commonly and is unanticipated by clinicians because of clozapine's significant anticholinergic activity. Case Report: A 34-year-old female developed clozapine-induced nocturnal, generalized hyperhidrosis following initial titration to 400 mg/day. Dose reduction did not decrease the side effect. Treatment with an anticholinergic medication could not be initiated because of constipation. Treatment with a beta blocker resulted in worsening of asthma. Treatment with a calcium channel blocker, diltiazem CD 180 mg/day, resulted in a significant reduction in hyperhidrosis. Conclusion: This case supports the use of calcium channel blockers to reduce clozapine-induced hyperhidrosis and offers an alternative to anticholinergic medications that may negatively impact clozapine tolerability.

Role of magnesium alone or in combination with diltiazem and/or amiodarone in prevention of atrial fibrillation following off-pump coronary artery bypass grafting.

Objectives: In this study the authors have tried to examine the role of magnesium alone or in combination with diltiazem and / or amiodarone in prevention of atrial fibrillation (AF) following off-pump coronary artery bypass grafting (CABG). Background: AF after CABG is common and contributes to morbidity and mortality. Various pharmacological preventive measures including magnesium, amiodarone, diltiazem, and combination therapy among others have been tried to lower the incidence of AF. Most of the studies have been performed in patients undergoing conventional on-pump CABG. In this uncontrolled trial, efficacy of magnesium alone or in combination with amiodarone and / or diltiazem has been studied in patients undergoing off-pump CABG. Methods: One hundred and fifty patients undergoing off-pump CABG were divided into 3 groups, Group M (n=21) received intraoperative magnesium infusion at 30mg/ kg over 1 hour after midline sternotomy; Group MD (n=78) received magnesium infusion in similar manner with diltiazem infusion at 0.05 µg/kg/hr throughout the intraoperative period; Group AMD (n=51) received preoperative oral amiodarone at a dose of 200 mg three times a day for 3 days followed by 200 mg twice daily for another 3 days followed by 200 mg once daily till the day of surgery along with magnesium and diltiazem infusion as in other groups. AF lasting more than 10 min or requiring medical intervention was considered as AF. Results: The overall incidence of postoperative AF was 12.6% with 11.7% in group AMD, 19% in group M, and 11.5% in group MD, which was not statistically significant. Conclusions: It is concluded that the use of amiodarone and/or diltiazem in addition to magnesium did not result in additional benefit of lowering the incidence of AF.

Comparison of the efficacy of diltiazem versus fluoxetine in the treatment of distal esophageal spasm: A randomized-controlled-trial.

BACKGROUND AND STUDY AIM: Distal esophageal spasm is an uncommon esophageal motility disorder presenting with non-cardiac chest pain and dysphagia. The main goal of therapy is symptom relief with pharmacologic, endoscopic, and surgical therapies. Pharmacologic treatment is less invasive and is the preferred method of choice. The purpose of this study was to compare the effectiveness of diltiazem versus fluoxetine in the treatment of distal esophageal spasm. PATIENTS AND METHODS: A total of 125 patients with distal esophageal spasm diagnosed using endoscopy, barium esophagogram, and manometry were evaluated. Patients were divided into diltiazem and fluoxetine groups and received a 2-month trial of diltiazem + omeprazole or fluoxetine + omeprazole, respectively. Of 125 patients, 55 were lost to follow up and 70 were eligible for final analysis. Clinical signs and symptoms were assessed before and after therapy using four validated questionnaires: Eckardt score, short form-36, heartburn score, and the hospital anxiety and depression scale. RESULTS: Both regimens significantly relieved symptoms (a decrease in mean Eckardt score of 2.57 and 3.18 for diltiazem and fluoxetine groups, respectively; and a decrease in mean heartburn score by 0.89 and 1.03 for diltiazem and fluoxetine groups, respectively). Patients' quality of life improved based on short form-36 (an increase in mean score of 2.37 and 3.95 for fluoxetine and diltiazem groups, respectively). There was no relationship between patients' improvement and severity of symptoms. Psychological findings based on the hospital anxiety and depression scale were inconsistent (a decrease in mean of 0.143 and 0.57 for fluoxetine and diltiazem groups, respectively; p > 0.05). CONCLUSION: Fluoxetine and diltiazem were effective for clinical symptom relief in patients with distal esophageal spasm, but were not promising for improving psychological symptoms. Neither regimen was superior in terms of efficacy. Consequently, it is key to consider side effects and comorbidities when choosing a therapy.