NIBEPIN TABLETS

Indications

• Hypertension
• Angina

Dosage

Children: Children 1 month to 11 years: Initially 100–200 micrograms/kg once daily; increased if necessary at intervals of 1–2 weeks up to a maximum of 5 mg once daily.

Adults: Initially, 5 mg once daily, increased if necessary to a maximum of 10 mg once daily.

Mechanism of action

Amlodipine inhibits the influx of calcium ions into vascular smooth muscle and cardiac muscle cells, leading to vasodilation and decreased myocardial oxygen demand.

Pharmacodynamics

Amlodipine causes a reduction in systemic vascular resistance and arterial pressure, resulting in decreased workload on the heart. It has a long duration of action due to its slow onset and prolonged effects.

Pharmacokinetics

Amlodipine is well absorbed orally, with peak plasma concentrations occurring 6-12 hours after administration. It has a half-life of approximately 30-50 hours, allowing for once-daily dosing. It is extensively metabolized in the liver and excreted primarily in the urine.

Contra-indications

• Cardiogenic shock
• Aortic stenosis

Adverse effects

• Asthenia
• Constipation
• Diarrhoea
• Drowsiness
• Dyspnoea
• Gastrointestinal disturbances

Interactions

• Grapefruit juice (severe increase in exposure)
• Enzalutamide (moderate decrease in exposure)
• Apalutamide (moderate decrease in exposure)
• Dronedarone (moderate increase in exposure)
• Antifungals (azoles) (moderate increase in exposure)
• Miconazole (moderate increase in exposure)
• Cobicistat (moderate increase in exposure)
• Crizotinib (moderate increase in exposure)
• Dabrafenib (moderate decrease in exposure)
• Idelalisib (moderate increase in exposure)

Precautions

• Caution in hepatic impairment (risk of increased exposure)
• Monitor for sudden withdrawal effects, which may exacerbate myocardial ischaemia

Pregnancy

Manufacturer advises caution due to limited data on safety.

Breast-feeding

Manufacturer advises to avoid; no information available.

Storage

Store at room temperature, away from moisture and heat.

Formulations

• Amlodipine 5mg/5ml oral solution (sugar-free)
• Amlodipine 10mg/5ml oral solution (sugar-free)
• Amlodipine 5 mg tablets
• Amlodipine 10 mg tablets

Indications

• Essential hypertension
• Migraine prophylaxis
• Hypertension in patients with renal impairment
• Adjunct treatment in stable mild to moderate heart failure
• Management of arrhythmias during anesthesia

Dosage

Children: Refer to the BNF for Children for specific dosing recommendations.

Adults: Initially 5 mg once daily, with a maximum of 40 mg daily depending on clinical response and tolerance.

Mechanism of action

Nebivolol selectively antagonizes beta-1 adrenergic receptors, leading to decreased heart rate, myocardial contractility, and blood pressure. Additionally, it stimulates beta-3 adrenergic receptors, causing increased nitric oxide production and subsequent vasodilation. This reduces vascular resistance and enhances cardiac output while minimizing adverse effects commonly associated with non-selective beta blockers.

Pharmacodynamics

Nebivolol decreases vascular resistance and increases stroke volume and cardiac output without negatively impacting left ventricular function. Its effects can persist for up to 48 hours after discontinuation of the drug. It possesses a wide therapeutic window, with typical doses ranging from 5 to 40 mg daily. Patients, especially those with coronary artery disease, should not stop treatment abruptly as this may exacerbate their condition. Additionally, diabetic patients should monitor blood glucose levels, as nebivolol may mask hypoglycemic symptoms.

Pharmacokinetics

Nebivolol is well absorbed and undergoes extensive first-pass metabolism. It has a half-life that allows for once-daily dosing, making it convenient for patient adherence. The drug is primarily metabolized by the liver, and its elimination is influenced by renal function. The pharmacokinetic profile supports its use in various patient populations, including the elderly, who may require dose adjustments.

Contra-indications

• Acute or decompensated heart failure requiring intravenous inotropes
• Severe bradycardia
• Heart block (greater than first degree) unless a functioning pacemaker is present
• Cardiogenic shock
• Severe hepatic impairment

Adverse effects

• Constipation
• Oedema
• Postural hypotension
• Dyspepsia
• Flatulence
• Skin reactions
• Palpitations
• Alopecia
• Arrhythmia
• Conjunctivitis
• Dry eyes
• Fatigue
• Thrombocytopenia
• Sexual dysfunction

Interactions

• Propafenone: Severe (increases exposure)
• Dacomitinib: Severe (increases exposure)
• Berotralstat: Moderate (increases exposure)
• Fedratinib: Moderate (increases exposure)
• Givosiran: Moderate (increases exposure)
• Panobinostat: Moderate (increases exposure)
• Bupropion: Unknown (increases exposure)
• Cinacalcet: Unknown (increases exposure)
• Terbinafine: Unknown (increases exposure)
• Ropeginterferonalfa: Unknown (increases exposure)

Precautions

• Use with caution in patients with diabetes, as beta-blockers may mask signs of hypoglycemia
• Monitor blood pressure and heart rate regularly
• Taper off the medication gradually to avoid exacerbation of coronary artery disease
• Caution in patients with a history of bronchospastic disease

Pregnancy

Use only if the benefits outweigh the risks, as safety in pregnancy has not been established.

Breast-feeding

Manufacturers advise avoidance due to potential effects on the infant.

Storage

Store in a cool, dry place away from direct sunlight. Keep out of reach of children.

Formulations

• Nebivolol 1.25 mg tablet
• Nebivolol 5 mg tablet
• Nebivolol 10 mg tablet
• Nebivolol solution for injection

Mechanism of action

**Mechanism of action on blood pressure** Amlodipine is considered a peripheral arterial vasodilator that exerts its action directly on vascular smooth muscle to lead to a reduction in peripheral vascular resistance, causing a decrease in blood pressure. Amlodipine is a dihydropyridine calcium antagonist (calcium ion antagonist or slow-channel blocker) that inhibits the influx of calcium ions into both vascular smooth muscle and cardiac muscle. Experimental studies imply that amlodipine binds to both _dihydropyridine_ and _nondihydropyridine_ binding sites, located on cell membranes. The contraction of cardiac muscle and vascular smooth muscle are dependent on the movement of extracellular calcium ions into these cells by specific ion channels. Amlodipine blocks calcium ion influx across cell membranes with selectivity. A stronger effect of amlodipine is exerted on vascular smooth muscle cells than on cardiac muscle cells. Direct actions of amlodipine on vascular smooth muscle result in reduced blood pressure. **Mechanism of action in angina** The exact mechanism by which amlodipine relieves the symptoms of angina have not been fully elucidated to this date, however, the mechanism of action is likely twofold: Amlodipine has a dilating effect on peripheral arterioles, reducing the total peripheral resistance (afterload) against which the cardiac muscle functions. Since the heart rate remains stable during amlodipine administration, the reduced work of the heart reduces both myocardial energy use and oxygen requirements. Dilatation of the main coronary arteries and coronary arterioles, both in healthy and ischemic areas, is another possible mechanism of amlodipine reduction of blood pressure. The dilatation causes an increase in myocardial oxygen delivery in patients experiencing coronary artery spasm (Prinzmetal's or variant angina) and reduces coronary vasoconstriction caused by smoking. Amlodipine is a dihydropyridine calcium antagonist (calcium ion antagonist or slow-channel blocker) that inhibits the transmembrane influx of calcium ions into vascular smooth muscle and cardiac muscle. Experimental data suggest that amlodipine binds to both dihydropyridine and nondihydropyridine binding sites. The contractile processes of cardiac muscle and vascular smooth muscle are dependent upon the movement of extracellular calcium ions into these cells through specific ion channels. Amlodipine inhibits calcium ion influx across cell membranes selectively, with a greater effect on vascular smooth muscle cells than on cardiac muscle cells. Negative inotropic effects can be detected in vitro but such effects have not been seen in intact animals at therapeutic doses. Serum calcium concentration is not affected by amlodipine. Within the physiologic pH range, amlodipine is an ionized compound (pKa=8.6), and its kinetic interaction with the calcium channel receptor is characterized by a gradual rate of association and dissociation with the receptor binding site, resulting in a gradual onset of effect. Recent studies have suggested that cytokines are capable of modifying cardiovascular function and that drugs used in the treatment of heart failure have various modulating properties on the production of cytokines. More recently, we have found that ouabain induces the production of cytokines. This study was performed to examine the effects of calcium channel blockers on the production of cytokines induced by a cardiac glycoside. Human peripheral blood mononuclear cells (PBMC) were obtained from healthy volunteers. PBMC were cultured in 0.1, 1, 10, and 30 umol/L amlodipine, diltiazem, and nifedipine in presence of 1 umol/L ouabain. After 24 hr of incubation, IL-1alpha, IL-1beta, IL-6, and TNF-alpha were measured in the culture supernatants by enzyme-linked immunosorbent assay. Ouabain induced the production of IL-1alpha, IL-1beta and IL-6, but not of TNF-alpha. Induction of IL-1beta was most prominent. The production of IL-1alpha, and IL-6 wa

Pharmacodynamics

**General pharmacodynamic effects** Amlodipine has a strong affinity for cell membranes, modulating calcium influx by inhibiting selected membrane calcium channels. This drug's unique binding properties allow for its long-acting action and less frequent dosing regimen,. **Hemodynamic effects** After the administration of therapeutic doses of amlodipine to patients diagnosed with hypertension, amlodipine causes vasodilation, which results in a reduction of supine and standing blood pressure. During these blood pressure reductions, there are no clinically significant changes in heart rate or plasma catecholamine levels with long-term use. Acute intravenous administration of amlodipine reduces arterial blood pressure and increases heart rate in patients with chronic stable angina, however, chronic oral administration of amlodipine in clinical studies did not cause clinically significant alterations in heart rate or blood pressures in patients diagnosed with angina and normal blood pressure. With long-term, once daily oral administration, antihypertensive effectiveness is maintained for at least 24 hours. **Electrophysiologic effects** Amlodipine does not change sinoatrial (SA) nodal function or atrioventricular (AV) conduction in animals or humans. In patients who were diagnosed with chronic stable angina, the intravenous administration of 10 mg of amlodipine did not cause clinically significant alterations A-H and H-V conduction and sinus node recovery time after cardiac pacing. Patients administered amlodipine with concomitant beta-blockers produced similar results. In clinical trials in which amlodipine was given in combination with beta-blockers to patients diagnosed with hypertension or angina, no adverse effects on electrocardiographic parameters were noted. In clinical studies comprised of angina patients alone, amlodipine did not change electrocardiographic intervals or produce high degrees of AV block. **Effects on angina** Amlodipine relieves the symptoms of chest pain associated with angina. In patients diagnosed with angina, daily administration of a single amlodipine dose increases total exercise time, the time to angina onset, and the time to 1 mm ST-segment depression on ECG studies, decreases anginal attack frequency, and decreases the requirement for nitroglycerin tablets.

Mechanism of action

Nebivolol is a highly selective beta-1 adrenergic receptor antagonist with weak beta-2 adrenergic receptor antagonist activity. Blocking beta-1 adrenergic receptors by d-nebivolol leads to decreased resting heart rate, exercise heart rate, myocardial contracility, systolic blood pressure, and diastolic blood pressure. The selectivity of d-nebivolol limits the magnitude of beta blocker adverse effects in the airways or relating to insulin sensitivity. Nebivolol also inhibits aldosterone, and beta-1 antagonism in the juxtaglomerular apparatus also inhibits the release of renin. Decreased aldosterone leads to decreased blood volume, and decreased renin leads to reduced vasoconstriction. l-nebivolol is responsible for beta-3 adrenergic receptor agonist activity that stimulates endothelial nitric oxide synthase, increasing nitric oxide levels; leading to vasodilation, decreased peripheral vascular resistance, increased stroke volume, ejection fraction, and cardiac output. The vasodilation, reduced oxidative stress, and reduced platelet volume and aggregation of nebivolol may lead to benefits in heart failure patients.

Pharmacodynamics

Nebivolol is a selective beta-1 adrenergic receptor antagonist that decreases vascular resistance, increases stroke volume and cardiac output, and does not negatively affect left ventricular function. It has a long duration of action as effects can be seen 48 hours after stopping the medication and a wide therapeutic window as patients generally take 5-40mg daily. Patients should not abruptly stop taking this medication as this may lead to exacerbation of coronary artery disease. Diabetic patients should monitor their blood glucose levels as beta blockers may mask signs of hypoglycemia.