Amlodipine-induced gingival enlargement: A case report

Gingival enlargements (GEs) can be caused by local, systemic diseases or drugs. Three molecules can be responsible of GEs: ciclosporin, phenytoin and calcium channel blockers (CCBs). We report the case of a 56-year-old male treated by Amlodipine, a CCB, for hypertension for many years and who recently developed a severe GE affecting both mandibular and maxillary arches inducing dental malposition. The histological examination showed non-specific inflammation with a predominance of lymphocytes. Amlodipine was suspected and suspended in agreement with his physician. One month later, the enlargement significantly reduced but GE was so severe and dental malposition so marked that all the teeth but the canines were extracted. No recurrence was noted one year later. This exceptional case should encourage every practitioner to be vigilant with patient treated with CCBs and their potential side effects and consequences.

Paraganglioma presenting as stress cardiomyopathy: case report and literature review

Pheochromocytoma/paraganglioma (PPGL) are neuroendocrine tumors that can secrete catecholamines. The authors describe a challenging case who presented as stress cardiomyopathy and myocardial infarction (MI). A 76-year-old man, with a medical history of Parkinson's disease, type 2 diabetes mellitus, hypertension, dyslipidaemia and a previous inferior MI in 2001, presented to the emergency department due to chest pain, headaches and vomiting. He also reported worsening blood glucose levels and increasing constipation over the preceding weeks. BP was 185/89 mmHg (no other relevant findings). EKG had ST segment depression in leads V2-V6, T troponin was 600 ng/L (<14) and the echocardiogram showed left ventricular hypokinesia with mildly compromised systolic function. Nevertheless, he rapidly progressed to severe biventricular dysfunction. Coronary angiogram showed a 90% anterior descendent coronary artery occlusion (already present in 2001), which was treated with angioplasty/stenting. In the following days, a very labile BP profile and unexplained sinus tachycardia episodes were observed. Because of sustained severe constipation, the patient underwent an abdominal CT that revealed a retroperitoneal, heterogeneous, hypervascular mass on the right (62 × 35 mm), most likely a paraganglioma. Urinary metanephrines were increased several fold. 68Ga-DOTANOC PET-CT scan showed increased uptake in the abdominal mass (no evidence of disease elsewhere). He was started on a calcium-channel blocker and alpha blockade and underwent surgery with no major complications. Eight months after surgery, the patient has no evidence of disease. Genetic testing was negative for known germline mutations. This was a challenging diagnosis, but it was essential for adequate cardiovascular stabilization and to reduce further morbidity. Learning points: PPGL frequently produces catecholamines and can manifest with several cardiovascular syndromes, including stress cardiomyopathy and myocardial infarction. Even in the presence of coronary artery disease (CAD), PPGL should be suspected if signs or symptoms attributed to catecholamine excess are present (in this case, high blood pressure, worsening hyperglycaemia and constipation). Establishing the correct diagnosis is important for adequate treatment choice. Inodilators and mechanical support might be preferable options (if available) for cardiovascular stabilization prior to alpha blockade and surgery. Laboratory interference should be suspected irrespective of metanephrine levels, especially in the context of treated Parkinson's disease.

Effect of acupuncture on blood pressure control in hypertensive patients

OBJECTIVE

To study the effect of acupuncture on blood pressure (BP) control in hypertensive patients.

METHODS

A total of 80 out-patients with primary hypertension at the family medicine unit and the social security unit were randomly and equally divided into an acupuncture plus medication group and a control group that received only medication. Patients of the acupuncture group were treated with acupuncture stimulation of Yinlinquan (SP 9), Zusanli (ST 36), Taichong (LR 3), Hegu (LI 4), Quchi (LI 11), Neiguan (PC 6) for 30 min, once per week, continuously for eight weeks. In addition, both groups received amlodipine (5 mg) once daily, continuously for eight weeks. Systolic BP (SBP), diastolic BP (DBP) and mean arterial BP (mABP) were recorded. Data were analyzed by Mann-Whitney U test.

RESULTS

SBP of the 40 cases in the acupuncture group significantly improved compared to the medication only group [Z =－ 4.265, P (2-tailed) = 0.001] and DBP of acupuncture group was lower than that of the control group (Z =－ 2.813, P = 0.005). mABP of acupuncture group was the marked improvement in the reduction of blood pressure to that of medication group in controlling blood pressure. (Z = －2.416, P = 0.016).

CONCLUSION

These results indicate that the effectiveness of acupuncture with the acupuncture group is superior to the only medication group in the control of hypertension.

Double trouble: two cases of dual adrenal pathologies in one adrenal mass

Context Adrenal incidentalomas (AI) represent an increasingly common problem in modern endocrine practice. The diagnostic approach to AIs can be challenging and occasionally reveals surprising features. Here we describe two rare cases of complex adrenal lesions consisting of phaeochromocytomas with synchronous metastases from extra-adrenal primaries. Case descriptions Patient 1 - a 65-year-old gentleman with a newly diagnosed malignant melanoma was found to harbour an adrenal lesion with suspicious radiographic characteristics. Percutaneous adrenal biopsy was consistent with adrenocortical adenoma. After excision of the skin melanoma and regional lymphatic metastases, he was followed up without imaging. Three years later, he presented with abdominal discomfort and enlargement of his adrenal lesion, associated with high plasma metanephrines. Adrenalectomy revealed a mixed tumour consisting of a large phaeochromocytoma with an embedded melanoma metastasis in its core. Patient 2 - a 63-year-old lady with a history of NF-1-related phaeochromocytoma 20 years ago and previous breast cancer presented with a new adrenal lesion on the contralateral side. Plasma normetanephrine was markedly elevated. Elective adrenalectomy revealed an adrenal tumour consisting of chromaffin cells intermixed with breast carcinoma cells. Conclusions Adrenal incidentalomas require careful evaluation to exclude metastatic disease, especially in the context of a history of previous malignancy. Adrenal biopsy provides limited and potentially misleading information. Phaeochromocytomas are highly vascularised tumours that may function as a sieve, extracting and retaining irregularly shaped cancer cells, thereby yielding adrenal masses with intriguing dual pathology. Learning points: Adrenal incidentalomas require careful evaluation focused on exclusion of underlying hormone excess and malignant pathology. Adrenal biopsy can be misleading and should only be considered in select cases. Phaeochromocytomas harbouring intratumoural metastases from other, extra-adrenal primary malignancies represent rare pathological entities that highlight the complexities that can be presented by adrenal tumours.

Vincristine combination with Ca+2 channel blocker increase antitumor effects

In this study, it was aimed to determine the effects of Amlodipine, a calcium channel blocker and vincristine (VCR) an antineoplastic, on human neuroblastomas using different doses. The cytotoxicity assays of the study were performed using the MTT method depending on time and concentration. After obtaining the mixture (up to 85% for SH-SY5Y) and sufficient branches (cortex neurons), the cells were treated with amlodipine (10 µM) and vincristine (0.5, 1 and 2 µg) at different concentrations for 24 h. MTT assay was performed by the commercially available kit (Sigma Aldrich, USA). Cells were harvested, washed and stained with PI and Annexin V, respectively, according to the manufacturer's protocol (Biovision, USA). Than analyzes were carried out. The results were quite impressive. When amlodipine (10 µM) was administered alone there was little change compared to the control. However, all doses of amlodipine (10 µM) and vincristine (0.5, 1 and 2 µg) were greater than the deaths in the doses alone (0.5, 1 and 2 µg) of vincristine alone. (P < 0.05). As a result, the combination of vincristine and amlodipine is more effective than vincristine alone in reducing the viability of cancer cells.

Determination of amlodipine and atorvastatin mixture by different spectrophotometric methods with or without regression equations

Four new, simple, and reproducible spectrophotometric methods were developed and validated for the simultaneous determination of Amlodipine (AML) and Atorvastatin (AT) in bulk powder and pharmaceutical dosage form. The four methods include two progressive and two successive resolution techniques. The two progressive methods are Absorbance Subtraction (AS) and Amplitude Modulation (AM), while the two successive methods are Constant Value (CV) and Concentration Value. In the Concentration Value method, the concentration of the drugs is determined from the graphical representation without the use of regression equations. Linearity range for the two progressive methods was from 5 μg/mL-35 μg/mL while for the two successive methods was from 5 μg/mL-55 μg/mL. The four methods were validated according to the ICH guidelines and were found to be accurate, precise, and selective. The methods were also applied for determination of the mixture in the marketed pharmaceutical dosage form. Results obtained were compared with reported methods. Also, One-way ANOVA statistical test was done between all the proposed spectrophotometric methods where no significant differences were found.

A Case of Severe, Refractory Hypotension After Amlodipine Overdose

Calcium channel blockers (CCBs) are responsible for a substantial portion of the mortality associated with cardiovascular medication overdose cases. Amlodipine, a dihydropyridine CCB, can cause prolonged hypotension in overdose. This report describes a severe amlodipine overdose case that was refractory to multiple therapeutic approaches. A 53-year-old male presented after ingesting eighty 10 mg amlodipine tablets in a suicide attempt. The patient was initially managed with calcium boluses, glucagon, multiple vasoactive agents, lipid emulsion infusions and hyperinsulinemic euglycemic therapy. Methylene blue boluses were initiated when hypotension persisted despite conventional treatments. Refractory hypotension prompted the use of plasmapheresis in an attempt to lower serum amlodipine levels. Finally, the patient was placed on extracorporeal membrane oxygenation (ECMO) to maintain perfusion while the effects of the amlodipine ingestion dissipated. Following an episode of asystole and pulseless electrical activity prior to the start of ECMO, the patient suffered an anoxic brain injury and suspected herniation prompting the family to withdraw medical care. There is limited evidence in the literature describing the refractory treatment modalities utilized in this patient. This report is unique as it describes the clinical course of a patient when a multitude of unique treatments were combined.

Fixed-Dose Combination Amlodipine/Celecoxib (Consensi) for Hypertension and Osteoarthritis

The US Food and Drug Administration recently granted an approved indication for the first fixed-dose combination antihypertensive (amlodipine) and nonsteroidal anti-inflammatory drug (celecoxib) for treatment of comorbid hypertension and osteoarthritis. This review summarizes available data on this combination product, to be marketed as Consensi (Kitov Pharmaceuticals, Ltd, Tel Aviv, Israel), and discusses its potential place in therapy.

Identification and structure elucidation of a new degradation impurity in the multi-component tablets of amlodipine besylate

New unknown impurity at m/z 421.15 was observed during the accelerated stability analysis (40 °C/75% relative humidity) in the multi-component tablets of amlodipine besylate by reversed-phase ultra-high performance liquid chromatography-mass spectrometry (UHPLC-MS). UHPLC-MS and nuclear magnetic resonance (NMR) techniques were employed to identify and fully characterize the degradation compound. The degradation product was unambiguously identified as 3-ethyl 5-methyl 4-(2-chlorophenyl)-6-methyl-2-(morpholin-2-yl)-1,4-dihydropyridine-3,5-dicarboxylate and mechanism of its formation was proposed. It was confirmed that the degradation product was formed by the reaction of amlodipine with formaldehyde originating from the excipients present in the dosage form.

A Case of Life-threatening Amlodipine and Atenolol Overdose

Treating a patient of amlodipine-atenolol poisoning is nightmare for a physician. In high dose both the drugs individually cause severe bradycardia and hypotension. In combination they cause severe cardiovascular depression. Here we report a case of 66-year-old obese, hypertensive, depressed male, who presented to emergency 9 hours after consumption of 25 tablets of amlodipine-atenolol (5 mg+50 mg). On evaluation, he had refractory bradycardia, hypotension and acute kidney injury (AKI). Eventually he developed cardiac arrest. He was revived after 5 minutes of cardio-pulmonary resuscitation (CPR). He was successfully managed with gastric lavage, fluids, inotropes, atropine, isoprenaline and subsequently with calcium gluconate infusion, high-dose insulin euglycemia therapy (HIET) and lipid emulsion therapy. Glucagon infusion was also planned but it was not available. Patient hemodynamics improved and on 8th day he got the discharge. Our case exemplifies the importance of timely and aggressive management of lethal overdose of amlodipine-atenolol poisoning.

How to cite this article: Tale S, Kumar M, Ghosh S, Bhalla A. A Case of Life-threatening Amlodipine and Atenolol Overdose. Indian J Crit Care Med 2019;23(6):281–283.

Can Amlodipine Improve the Pre-ovulatory Follicle Blood Flow in Women with Polycystic Ovarian Syndrome?

BACKGROUND

A reduction in intra-ovarian vascular resistance is necessary to achieve pregnancy in a natural cycle. The aim of this RCT was to detect whether a vasodilator calcium channel blocker, amlodipine, could increase the pre-ovulatory follicular blood flow, enhance follicular maturation in women with PCOS and improve ovulatory outcome.

METHODS

Sixty women received induction by clomiphene citrate (CC); thirty were given amlodipine (Amlodipine group) and the other 30 women were given placebo (Placebo group). The pattern of pre-ovulatory follicle blood flow was studied by color and power Doppler ultrasonography pre and post drug administration. Independent t-test was used to compare mean values of the 2 groups. The p<0.05 is considered statistically significant.

RESULTS

When comparing the Doppler effect of amlodipine versus placebo in the treatment cycle, it was found that mean value of ovarian arteries (OA) pulsatility index was lower in amlodipine group but it didn't reach statistical significance (p= 0.063); however, the mean value of OA resistance index reached statistical significance (p=0.028) in amlodipine group. Moreover, in the second cycle, endometrial thickness was significantly higher (p=0.006) in women of the amlodipine group when compared to those of the placebo group. At least one sonographically detectable mature follicle (≥18 mm) was observed in 54.5% (36/66) during the first cycle. At the second cycle, this proportion significantly rose to 86.7% (26/30) in the amlodipine group, but marginally and non-significantly to 56.7% (17/30) in the placebo group.

CONCLUSION

Amlodipine as calcium channel blocker was proved to have a role in improving ovarian blood flow at the time of ovulation and enhancing follicular maturation and thus, it may increase the chances of conception.

A comparison of the effects of perindopril arginine and amlodipine on choroidal thickness in patients with primary hypertension

Background/aim

This study aimed to investigate the effects of two different medical treatment options on choroidal thickness (CT) in patients with primary hypertension.

Materials and methods

Forty newly diagnosed primary hypertension patients and 21 healthy volunteers were included. The patients were randomly divided into two subgroups. Group I started on perindopril arginine and Group II started on amlodipine. Submacular CT using optical coherence tomography (OCT) was measured before treatment and at the third and sixth months after treatment.

Results

Initial mean arterial pressure (MAP) values in Groups I and II and the control group were 113.4, 109.8, and 89.4 mmHg, respectively, and mean CT values were 257.9, 286.5, and 300.9 μm. Mean MAP values in Groups I and II and the control group at the sixth month after treatment were 99.7, 99.6, and 90.2 mmHg, respectively, and mean CT values were 293.1, 286, and 297.4 μm. Analysis of the changes occurring during the study revealed significant variation in MAP in Groups I and II, and in CT in Group I only.

Conclusion

A gradual increase in CT developed with perindopril arginine therapy in patients with primary hypertension, while no significant change occurred in CT in the amlodipine group.

The extent of drug-drug interaction between amlodipine and activated charcoal is attenuated by food intake in rats

Activated charcoal decreases gastrointestinal absorption of concomitantly administered drugs. The absorption of amlodipine (AML) was reported as almost completely attenuated by 25 g of activated charcoal under a fasted condition, but not affected by 2 g of activated charcoal under a fed condition. However, it is not clear whether this difference resulted from the food intake or the dose of activated charcoal. The aim of this study was to quantitatively evaluate the effect of food intake on drug interactions caused by adsorption to activated charcoal in the gastrointestinal tract in rats. The rats were orally administered 0.08 mg/kg of AML, with or without 33 mg/kg of activated charcoal, under the fasted or fed condition and the plasma concentration profiles of AML were monitored. For the fed group, the standard breakfast used in clinical studies was smashed and administered at a dose of 11 g/kg. The AUC value of AML under the fasted condition was significantly decreased to 24.8% by coadministration of activated charcoal. On the other hand, activated charcoal moderately decreased the AUC value of AML to 74.8% under the fed condition. These results suggest that the extent of drug interactions caused by activated charcoal is attenuated by food intake.

Efficacy of zofenopril in combination with amlodipine in patients with acute myocardial infarction: a pooled individual patient data analysis of four randomized, double-blind, controlled, prospective studies

OBJECTIVE

In the four SMILE (Survival of Myocardial Infarction Long-Term Evaluation) studies, early administration of zofenopril in acute myocardial infarction (AMI) showed beneficial effects as compared to placebo and other angiotensin converting enzyme inhibitors (ACEIs). This study investigated whether the concomitant administration of the dihydropyridine calcium channel-blocker amlodipine may improve zofenopril efficacy to prevent cardiovascular events in post-AMI patients.

METHODS

This was a post-hoc analysis of pooled individual patient data from the four large randomized SMILE studies. The primary endpoint was the 1-year combined occurrence of death or hospitalization for cardiovascular causes.

RESULTS

In total, 3488 patients were considered, 303 (8.7%) treated with concomitant amlodipine. Baseline systolic blood pressure and prevalence of metabolic syndrome were higher in amlodipine treated patients. The 1-year occurrence of major cardiovascular outcomes was significantly reduced in patients receiving concomitant treatment with amlodipine (hazard ratio, HR = 0.66; and 95% confidence interval, CI = 0.44-0.98; p = .039). After accounting for treatment with amlodipine, the risk of cardiovascular events was significantly reduced with zofenopril compared to placebo (HR = 0.78; 95% CI = 0.63-0.97; p = .026]. Among ACEI-treated patients, the zofenopril plus amlodipine combination reduced the risk of cardiovascular events by 38%, compared to the combination of other ACEIs plus amlodipine [HR = 0.76; 95% CI = 0.61-0.94); p = .013). The prognostic benefit of concomitant treatment with zofenopril plus amlodipine was independent from blood pressure lowering.

CONCLUSIONS

Zofenopril had a positive impact on prognosis in post-AMI patients, compared to other ACEIs. Concomitant administration of amlodipine may help to reduce the risk of cardiovascular events at 1 year.

Low Baseline High-Sensitive C-Reactive Protein is Associated with Coronary Atherosclerosis Regression: Insights from the MILLION Study

Aim: The prospective, randomized, multicenter Myocardial Ischemia Treated with Percutaneous Coronary Intervention and Plaque Regression by Lipid Lowering & Blood Pressure Controlling assessed by Intravascular Ultrasonography (MILLION) study demonstrated that combined treatment with atorvastatin and amlodipine enhanced coronary artery plaque regression. Although the baseline high-sensitive C-reactive protein (hs-CRP) reportedly plays an important role in atherogenesis, few data exist regarding the relationship between hs-CRP and plaque regression in patients receiving a combined atorvastatin and amlodipine therapy.

Methods: A total of 68 patients (male, 55; mean age, 64.2 years) with baseline and follow-up 3-dimensional intravascular ultrasound examinations in the MILLION study were stratified by baseline hs-CRP level quartiles. The serial measurements of lipid, blood pressure, and percentage changes in the plaque volume were compared between the groups, and the factors associated with the percentage change in the plaque volume were assessed.

Results: There were no significant between-group differences in the extent of change in low-density lipoprotein cholesterol (LDL-C) or systolic and diastolic blood pressure after 18–24 months of treatment. The percentage change in the plaque volume showed a linear association with the baseline hs-CRP (p for trend < 0.05); however, there was no correlation with changes in LDL-C or systolic and diastolic blood pressure. In the multiple regression analysis, the baseline hs-CRP level was independently associated with the percentage change in the plaque volume (β = 0.29, p = 0.022).

Conclusions: Coronary plaque regression was associated with the baseline hs-CRP level in patients treated with a combined lipid- and blood pressure-lowering therapy.

An Update on Calcium Channel Blocker Toxicity in Dogs and Cats

The widespread use and availability of calcium channel blockers in human and veterinary medicine pose a risk for inadvertent pet exposure to these medications. Clinical signs of toxicosis can be delayed by many hours after exposure, with lethargy, hypotension, and cardiac rhythm changes as the predominant signs. Prompt decontamination and aggressive treatment using a variety of modalities may be necessary to treat patients exposed to calcium channel blockers. The prognosis of an exposed patient depends on the dose of the ingested calcium channel blockers, promptness of decontamination and other treatment measures, severity of clinical signs, and response to treatment.

Effect of drug amlodipine on the charged lipid bilayer cell membranes DMPS and DMPS + DMPC: a molecular dynamics simulation study

In this work, the effects of the anti-hypertensive drug amlodipine in native and PEGylated forms on the malfunctioning of negatively charged lipid bilayer cell membranes constructed from DMPS or DMPS + DMPC were studied by molecular dynamics simulation. The obtained results indicate that amlodipine alone aggregates and as a result its diffusion into the membrane is retarded. In addition, due to their large size aggregates of the drug can damage the cell, rupturing the cell membrane. It is shown that PEGylation of amlodipine prevents this aggregation and facilitates its diffusion into the lipid membrane. The interaction of the drug with negatively charged membranes in the presence of an aqueous solution of NaCl, as the medium, is investigated and its effects on the membrane are considered by evaluating the structural properties of the membrane such as area per lipid, thickness, lipid chain order and electrostatic potential difference between bulk solution and lipid bilayer surface. The effect of these parameters on the diffusion of the drug into the cell is critically examined and discussed.

Effects of Amlodipine on Bone Metabolism in Orchidectomised Spontaneously Hypertensive Rats

Spontaneously hypertensive rats (SHR) represent a model of essential hypertension. We studied the effect of amlodipine (AML) on bone markers, bone mineral density (BMD), and biomechanical properties of osteopenic bone induced by orchidectomy in male SHR. Rats were allocated to 3 groups and were sacrificed after 12 weeks: sham-operated control; orchidectomised control; and orchidectomised receiving a diet supplemented with AML. Indicators of bone turnover were assessed in bone homogenate, BMD was measured by dual energy X-ray absorptiometry, and the femurs were subjected to biomechanical testing. Long-term AML administration does not have a negative impact on bone metabolism and density in male SHR.

Magnesium taurate attenuates progression of hypertension and cardiotoxicity against cadmium chloride-induced hypertensive albino rats

The present study was designed to evaluate the antihypertensive activity and cardioprotective effects of magnesium taurate against cadmium chloride (CdCl₂)-intoxicated albino rats. Sprague Dawley male albino rats (120-150 g) were divided into five groups having six animals in each group. Hypertension and cardiotoxicity were induced in animals by administration of CdCl₂ (0.5 mg/kg/day, i.p.) for four weeks. Magnesium taurate (2 and 4 mg/kg/day) was administered orally after induction of hypertension (after two weeks) in their respective groups concurrently with CdCl₂ for next two weeks. Amlodipine (3 mg/kg/day, p.o.) was used as a standard and administered after induction of hypertension. Blood pressure was monitored biweekly by using non-invasive blood pressure system and biochemical parameters and histopathology of the heart were evaluated after four weeks of the experimental protocol. During the four weeks of the experimental protocol, the toxic control group showed significant elevation of systolic and diastolic blood pressure concomitant with augmentation of cardiotoxicity as indicated by reduction in myocardial antioxidants including glutathione peroxidase, catalase, superoxide dismutase, reduced glutathione and increased malondialdehyde level in heart as compared to the normal group. The oral administrations of magnesium taurate significantly restored the blood pressure, myocardial antioxidants and malondialdehyde level as compared to toxic control group. In addition, histopathological examination showed that magnesium taurate treatments substantially reduced the myocardial damages against CdCl₂ treatment. The results suggest that magnesium taurate has prominent antihypertensive and cardioprotective activity via its potent antioxidant activity and can be used as a nutrition supplement to improve the cardiovascular health.

Guiding dose adjustment of amlodipine after co-administration with ritonavir containing regimens using a physiologically-based pharmacokinetic/pharmacodynamic model

Amlodipine, a commonly prescribed anti-hypertensive drug, shows increased systemic exposure with cytochrome P450 (CYP) 3A inhibitors. Ritonavir (RTV) is a potent mechanism-based and reversible CYP3A inhibitor and moderate inducer that is used as a pharmacokinetic enhancer in several antiviral treatment regimens. Drug-drug interaction (DDI) between RTV and amlodipine is due to mixed inhibition and induction of CYP3A4, which is challenging to predict without a mechanistic model that accounts for the complexity of both mechanisms occurring simultaneously. A novel physiologically-based pharmacokinetic (PBPK) model was developed for amlodipine, and the model was verified using published clinical PK and DDI data. The verified amlodipine PBPK model was linked to a pharmacodynamics model that describes changes in systolic blood pressure (SBP) during and after co-administration with RTV. The magnitude and time course of RTV effects on amlodipine plasma exposures and SBP were evaluated, to provide guidance on dose adjustment of amlodipine during and after co-administration with RTV-containing regimens. Model simulations suggested that the increase in amlodipine's plasma exposure by RTV diminishes by approximately 80% within 5 days after the last dose of RTV. PBPK simulations suggested that resuming a full dose of amlodipine [5 mg once daily (QD)] immediately after RTV's last dose would decrease daily average SBP by a maximum of 3.3 mmHg, while continuing with the reduced dose (2.5 mg QD) for 5 days after the last dose of RTV would increase daily average SBP by a maximum of 5.8 mmHg. Based on these results, either approach of resuming amlodipine's full dose could be appropriate when combined with appropriate clinical monitoring.

Validated LC-MS/MS method for the determination of amlodipine enantiomers in rat plasma and its application to a stereoselective pharmacokinetic study

A rapid and sensitive method was established to determine amlodipine enantiomers using liquid chromatography-tandem mass spectrometry (LC-MS/MS). Stereoselective separation was performed on CHIRALCEL OZ-RH column (150 mm × 4.6 mm i.d., 5 μm) with acetonitrile-water (10 mM ammonium acetate, 0.5% ammonia solution) (95:5, v/v) at a flow rate of 0.5 mL/min. The substances were detected by mass spectrometer equipped with an electrospray ionization source interface in positive ion mode. Multiple reaction monitoring was selected with the transition of the m/z 409.1 → 238.0 for amlodipine enantiomers and m/z 237.0 → 194.1 for carbamazepine (IS) respectively. Calibration curves were linear at the range of 0.9375-120 ng/mL for both isomers with r > 0.99, while using a lower sample volume (50 μL) compared with previously reported enantiospecific methods The accuracy was at the range of 84.1-119.0% for R-amlodipine, and 87.4-118.2% for S-amlodipine, respectively. The within- and between-run precision (CV%) was within 10% in all cases for both enantiomers. Enantiomers were stable under different conditions, e.g. processed sample, short-term, residue, long-term and freeze/thaw. The LC-MS/MS method was successfully applied in pharmacokinetic study of amlodipine enantiomers in rats. It was observed the concentration of the S- amlodipine was significantly higher than that of the R-amlodipine in racemate-treated group. And there was no significant difference in the pharmacokinetic profiles of the S-amlodipine between the 10 mg/kg racemate- and 5 mg/kg S-amlodipine-treated groups. In addition, it was the first time to find that the main pharmacokinetic parameters (AUC_(0-t), AUC_(0-∞) and C_max) of R-amlodipine were significantly lower in the 5 mg/kg R-amlodipine-treated group compared with the racemate-treated group.

Drug-induced atypical hyperplasia enveloping salivary gland malignancy

Gingival enlargement is a very common side effect associated with the administration of several drugs, mainly anticonvulsants, calcium channel blockers (CCBs), and immunosuppressants. Amlodipine (a CCB) is a safe antihypertensive drug with a longer duration of action. Gingival enlargement induced by amlodipine is less prevalent among CCBs. Since the pathogenesis is not well understood, it is still a challenge for clinicians to diagnose and manage cases effectively. This case presents an atypical unilateral palatal gingival enlargement in a 61-year-old hypertensive female taking amlodipine. Difficulty for a pathologist in diagnosing in spite of repeated sample submission from the lesion and repeated failure for the operator to reach the underlying pathology due to amlodipine-induced hyperplasia have also been discussed in this case report.

Effectiveness of a Fixed-Dose, Single-Pill Combination of Perindopril and Amlodipine in Patients with Hypertension: A Non-Interventional Study

INTRODUCTION

We conducted a prospective, non-interventional, multicenter study to examine the effect of a fixed-dose combination of perindopril/amlodipine in patients with arterial hypertension.

METHODS

Patients who were previously untreated or required a change in medication were treated with a fixed combination of perindopril/amlodipine (3.5/2.5 or 7.0/5.0 mg) for 12 weeks. Changes in office, home and ambulatory blood pressure (BP) were recorded. Adherence was assessed by the Hill-Bone medication adherence scale.

RESULTS

Overall, 1814 patients (mean age 60.0 ± 13.4 years) were included in 614 German practices, and data of 1770 patients were analyzed. At study entry, 97.7% of patients received perindopril/amlodipine at a daily dose of 3.5 mg/2.5 mg, and 47.9% of patients remained on this dose during the study period. Treatment with perindopril/amlodipine decreased mean office BP from 163.7/95.4 to 133.6/80.3 mmHg (p < 0.0001), resulting in a hypertension control rate of 69.1%. Blood pressure control was comparable in previously untreated and treated patients (70.3 vs. 68.1%), and in younger and older patients (70.6 < 65 vs. 66.3% ≥ 65 years). Ambulatory BP measurements were available in a subgroup of patients (n = 167), and mean 24 h ambulatory BP decreased from 150.6 ± 12.6/88.9 ± 8.8 to 132.4 ± 11.9/79.4 ± 8.5 mmHg (p < 0.0001). Furthermore, the proportion of patients with severe hypertension European Society of Hypertension/European Society of Cardiology (ESH/ESC) grade II or III decreased from 64.4 to 3.9%, and patients with pre-existing isolated systolic hypertension (n = 284) converted to normal BP in 67.6% of cases. Nearly half of the patients (47.2%) were perfectly adherent during the study. In previously treated patients, the percentage of patients with perfect adherence increased from 20.6% prior to study to 43.5% at final visit (p < 0.0001). Adverse drug reactions were documented for 4.9% of patients.

CONCLUSION

A fixed-dose combination of perindopril/amlodipine shows significant blood pressure reduction and improvement in medication adherence in a primary care setting.

TRIAL REGISTRATION

ISRCTN26323538.

FUNDING

Servier Deutschland GmbH.

Chlorthalidone, not hydrochlorothiazide, is the right diuretic for comparison

We have read the study design "Comparison of effects between calcium channel blocker and diuretics in combination with angiotensin II receptor blocker on 24-h central blood pressure and vascular hemodynamic parameters in hypertensive patients: study design for a multicenter, double-blinded, active controlled, phase 4, randomized trial" by Oh GC, et al. with interest. The authors aim to compare the efficacy of amlodipine or hydrochlorothiazide (HCTZ) with an ARB. However, we wish to highlight that chlorthalidone (CTD) is the evidence-based and recommended anti-hypertensive diuretic, and should replace HCTZ in the trial to effectively compare efficacy against the CCB amlodipine.

Application of an LC-MS/MS method for the analysis of amlodipine, valsartan and hydrochlorothiazide in polypill for a bioequivalence study

A sensitive and selective method has been proposed for the simultaneous determination of amlodipine (AML), valsartan (VAL) and hydrochlorothiazide (HCTZ) in human plasma by liquid chromatography–tandem mass spectrometry (LC–MS/MS). The analytes and their deuterated analogs were quantitatively extracted from 100 µL human plasma by solid phase extraction on Oasis HLB cartridges. The chromatographic separation of the analytes was achieved on a Chromolith RP_18e (100 mm × 4.6 mm) analytical column within 2.5 min. The resolution factor between AML and VAL, AML and HCTZ, and VAL and HCTZ was 2.9, 1.5 and 1.4, respectively, under isocratic conditions. The method was validated over a dynamic concentration range of 0.02–20.0 ng/mL for AML, 5.00–10,000 ng/mL for VAL and 0.20–200 ng/mL for HCTZ. Ion-suppression/enhancement effects were investigated by post-column infusion technique. The mean IS-normalized matrix factors for AML, VAL and HCTZ were 0.992, 0.994 and 0.998, respectively. The intra-batch and inter-batch precision (% CV) across quality control levels was ≤ 5.56% and the recovery was in the range of 93.4%–99.6% for all the analytes. The method was successfully applied to a bioequivalence study of 5 mg AML + 160 mg VAL + 12.5 mg HCTZ tablet formulation (test and reference) in 18 healthy Indian males under fasting. The mean log-transformed ratios of C_max, AUC_0–120h and AUC_0-inf and their 90% CIs were within 90.2%–102.1%. The assay reproducibility was demonstrated by reanalysis of 90 incurred samples.