Effect of Amlodipine in Stroke and Myocardial infarction: A Systematic Review and Meta-analysis

The evidence base of the 10 most prescribed drugs in England, France, and the United States: a scoping review

OBJECTIVES

To evaluate whether there is evidence of efficacy of the most commonly used medications in their primary indications.

STUDY DESIGN AND SETTING

This scoping review was executed using the Cochrane Library and MEDLINE databases up to May 2023. The 10 most prescribed medications in England, France, and the United States were identified using country-specific public databases. Up to 3 common indications in primary care were defined for each medication, based on a survey of general practitioners. The outcomes were determined by the authors to be patient-important outcomes, with placebo as the comparator. Two investigators independently conducted searches, following a predefined algorithm, to identify randomized controlled trials or meta-analyses of randomized controlled trials assessing the efficacy of these medications for each indication. The risk of bias was assessed using the ROBIS or ROB 2.0 tools.

RESULTS

We identified 21 drugs, covering 56 indications and 114 outcomes. Sixty-seven percent of the evaluated medications demonstrated efficacy for at least one outcome in at least one of the sought indications. Overall, evidence of efficacy was found for 48% of the indications. There was no study evaluating the efficacy of amoxicillin and salbutamol. For other drugs such as phloroglucinol or cholecalciferol, available studies suggested an absence of efficacy in the most common indications.

CONCLUSION

This study underscores the lack of data regarding the level of evidence for the most prescribed medications. Limitations include the choice of outcomes, and the understanding that the absence of evidence is not synonymous with the absence of efficacy.

Amlodipine in the current management of hypertension

Hypertension is the leading cause of death worldwide, affecting 1.4 billion people. Treatment options include the widely used calcium channel blockers, among which amlodipine, a dihydropyridine, has unique characteristics that distinguish it from other drugs within this class. This review aims to provide an updated overview of the evidence supporting the use of amlodipine over the past 30 years and highlights its cardiovascular benefits in current hypertension management. Amlodipine has low renal clearance (7 mL/min/mg) and long half-life (35-50 h) and duration of action, which allows it to sustain its anti-hypertensive effect for more than 24 h following a single dose. Additionally, blood pressure (BP) control is maintained even when a dose has been missed, providing continuous protection in case of incidental noncompliance. It has proven to reduce BP variability and successfully lower BP. Amlodipine also controls BP in patients with a systolic/diastolic BP of 130/80 mm Hg or higher, diabetes, or chronic kidney disease without worsening glycemic or kidney function. Additionally, amlodipine is a wise choice for older adults due to its ability to control BP and protect against stroke and myocardial infarction. Side effects of amlodipine include edema, palpitations, dizziness, and flushing, which are more common with the higher dose of 10 mg. Amlodipine is cost effective and predicted to be cost saving when compared with usual care.

Blood Pressure Control and Prescription Pattern of Antihypertensive Drugs in Adherence to the 2020 International Society of Hypertension (ISH) Global Hypertension Practice Guidelines in Saudi Arabia: A Retrospective Study

Background Hypertension is the leading risk factor for cardiovascular disease and death. Appropriate treatment of hypertension is necessary to reduce mortality. A prescription-based study is one of the most influential and helpful methods to examine physicians' irrational prescribing practices. This study was designed to investigate the antihypertensive prescription of physicians and their adherence to the treatment guidelines, as well as the blood pressure (BP) control rate in a general hospital in the Kingdom of Saudi Arabia. Methodology A retrospective, cross-sectional study was conducted between February 2020 and June 2021 in an outpatient department. Patients diagnosed with hypertension as per the 2020 International Society of Hypertension guidelines and those who received antihypertensive drugs were included. Study data included prescriptions, patient's age, duration of hypertension, comorbidities, BP, drug therapy type, and antihypertensive class. Results Overall, angiotensin-converting enzyme inhibitors/angiotensin II receptor blockers (67.1%) were the most prescribed agents, followed by dihydropyridine-calcium channel blockers (62.6%), diuretics (26.1%), and β-blockers (10.1%). Comorbid and stage 2 hypertensive patients mainly received combination therapy (51.6%) rather than monotherapy (48.4%). The study revealed an 83.5% prescription adherence to the treatment guidelines. However, non-adherence was encountered in monotherapy, polytherapy, and elderly-treated patient groups. A 66.4% (at target BP in all cases <140/90 mmHg) and 39.3% (at target BP in comorbid patients <130/80 mmHg) rate of BP control was observed. Furthermore, the rate of BP control was significantly associated with prescription adherence (χ² = 71.316; p < 0.001). Conclusions The degree of prescription adherence and rate of BP control were found to be compatible with other published hypertension studies. However, considerable scope exists for improvement in rational drug utilization and rate of BP control, particularly in high-risk patients. Therefore, treatment guidelines must be followed by clinicians to achieve BP goals and reduce cardiovascular events among the Saudi population.

Pharmacokinetic Drug Interaction Between Amlodipine and Tadalafil: An Open-Label, Randomized, Multiple-Dose Crossover Study in Healthy Male Volunteers

Purpose

The combined administration of tadalafil, a phosphodiesterase-5 inhibitor, and amlodipine, a calcium channel blocker, can be a promising therapeutic option for hypertension patients with erectile dysfunction. This study aimed to examine the pharmacokinetic drug interaction between tadalafil and amlodipine and the tolerability of their combined administration in healthy male subjects.

Subjects and Methods

Healthy volunteers (N = 24) were randomly assigned to one of the six sequences that consisted of three treatments: tadalafil (5 mg) alone, amlodipine (10 mg) alone, and tadalafil plus amlodipine. The study drugs were administered orally for 9 d, and the collected serial blood samples were analyzed up to 72 h after the last dosing. Pharmacokinetic parameters were calculated using non-compartmental analysis.

Results

For tadalafil, geometric mean ratios (GMRs) (90% confidence interval (CI)) of the combined therapy over the monotherapy were 1.57 (1.46–1.68) for AUC_τ,ss and 1.34 (1.24–1.45) for C_max,ss. For amlodipine, the GMRs (90% CI) of AUC_τ,ss and C_max,ss were 0.93 (0.90–0.97) and 0.95 (0.91–0.99), respectively. The severity of all observed adverse events (AEs) related to the study drugs was mild, and the frequency of AEs of the combined administration was not significantly different from the monotherapy.

Conclusion

A substantial pharmacokinetic drug interaction between tadalafil and amlodipine was observed with respect to the concentration of tadalafil when administered concomitantly. However, the dose range of the combined administration of tadalafil and amlodipine in the present study was well tolerated by the subjects.