Product Overview
[Drug Name]
Generic Name: Metoprolol Succinate Sustained-Release Tablets
Trade Name: HuaMeiKe Metoprolol Succinate Sustained-Release Tablets, 47.5mg*7 Tablets
Pinyin Full Code: HuaMeiKe ZuoZuoSuanMeiTuoLuoErHuanShiPian, 47.5mg*7 Tablets
[Main Ingredient]
The main ingredient of this product is metoprolol succinate. Chemical Name: 1-Isopropylamino-3-[p-(2-methoxyethyl)phenoxy]-2-propanol L(+)-succinate. Molecular Formula: (C₁₅H₂₅NO₃)₂·C₄H₆O₄. Molecular Weight: 652.82
[Properties]
This product is a white or off-white film-coated tablet. It appears white after removal of the coating.
[Indications/Main Functions]
Hypertension. Angina pectoris. Stable chronic heart failure with symptoms of left ventricular systolic dysfunction.
[Precautions]
Intravenous verapamil should not be administered to patients receiving beta-blockers. Metoprolol may exacerbate symptoms of peripheral vascular disorders, such as intermittent claudication. Caution is advised in patients with severe renal impairment, acute conditions associated with metabolic acidosis, and when used concomitantly with digitalis. Patients with Prinzmetal's angina may experience increased frequency and severity of angina attacks after taking beta-blockers due to alpha-receptor-mediated coronary vasoconstriction. Therefore, non-selective beta-blockers should not be used in such patients. Selective beta-1 blockers should also be used with caution. Patients with bronchial asthma or other chronic obstructive pulmonary disease should receive adequate bronchodilator therapy concurrently, and the dose of beta-2 agonists may need to be increased. At therapeutic doses, metoprolol has a weaker contractile effect on bronchial smooth muscle than non-selective beta-blockers, a property that allows its concomitant use with beta-2 agonists in patients with bronchial asthma or other significant obstructive pulmonary diseases. Beta-blockers may mask tachycardia caused by hypoglycemia but do not significantly affect other symptoms, such as dizziness and sweating. Metoprolol therapy has a lower risk of affecting glucose metabolism or masking hypoglycemia than non-selective beta-blockers, and blood glucose returns to normal levels more quickly. Beta-adrenergic receptor blockers may mask some clinical signs of hyperthyroidism (such as tachycardia). Abrupt discontinuation of beta-blocker therapy may lead to a thyroid crisis. In rare cases, pre-existing moderate atrioventricular conduction abnormalities may worsen (possibly leading to atrioventricular block). Beta-blocker therapy may interfere with the treatment of allergic reactions, and conventional doses of epinephrine do not always yield the desired effect. Patients with pheochromocytoma who are taking metoprolol succinate should consider concomitant use of an alpha-blocker. Limited controlled clinical trial data are available on the efficacy and safety of metoprolol in patients with severe, symptomatic stable heart failure (NYHA IV heart function); therefore, treatment of such patients should only be initiated by experienced and well-trained physicians. Clinical studies of heart failure typically exclude patients with symptomatic heart failure associated with acute myocardial infarction and unstable angina. Therefore, data on the efficacy and safety of this drug in the treatment of patients with concurrent acute myocardial infarction and heart failure are lacking. This drug is contraindicated in patients with unstable, decompensated heart failure. Abrupt discontinuation of metoprolol succinate extended-release tablets should be avoided, as this may worsen chronic heart failure and increase the risk of myocardial infarction and sudden death, particularly in high-risk patients. Therefore, this drug should be withdrawn gradually, over at least two weeks, with the dose reduced by half each time until the final dose is half a 23.75 mg tablet. The last dose should be given at least four days prior to discontinuation. If symptoms develop, a more gradual withdrawal is recommended. If this drug is to be discontinued before surgery, it must be discontinued at least 48 hours in advance, unless there are specific circumstances, such as thyrotoxicosis and pheochromocytoma. The anesthesiologist should be informed before surgery that the patient has been receiving metoprolol succinate extended-release tablets. Discontinuation of beta-blocker therapy is not recommended for patients undergoing surgery. Avoid rapid initiation of high-dose metoprolol in patients undergoing noncardiac surgery, as rapid initiation of high-dose metoprolol therapy may result in bradycardia, hypotension, and stroke, including possible death in patients with cardiovascular risk factors. Use with caution in athletes. Effects on Driving and Operating Machinery: Dizziness and fatigue may occur during treatment with this drug; therefore, caution should be exercised during activities requiring concentration, such as driving and operating machinery.
Drug Interactions
Cardiogenic shock. Sick sinus syndrome (without permanent pacemaker protection). Second- and third-degree atrioventricular block. Patients with unstable, decompensated heart failure (pulmonary edema, hypoperfusion, or hypotension), or those receiving continuous or intermittent inotropic therapy with beta-agonists. Symptomatic bradycardia or hypotension. This drug should not be administered to patients with suspected acute myocardial infarction and a heart rate <45 beats/min, a P-Q interval >0.24 seconds, or a systolic blood pressure <100 mmHg. Patients with heart failure indications whose supine systolic blood pressure is consistently below 100 mmHg on multiple occasions should have their suitability for this drug reassessed before starting treatment. This also applies to patients with severe peripheral vascular disease with a risk of gangrene. Patients with allergies to any of the ingredients in this drug or other beta-blockers.
Specifications:
47.5 mg x 7 tablets
Dosage and Administration:
Oral, once daily, preferably in the morning. The tablets may be broken but not chewed or crushed. They should be taken with at least half a cup of liquid. Concomitant food intake does not affect its bioavailability. Dosage should be individualized to avoid bradycardia. The following are effective dosing guidelines: Hypertension: 47.5-95 mg once daily. Patients who do not respond to 95 mg may combine with other antihypertensive medications, preferably diuretics and dihydropyridine calcium channel blockers, or increase the dose. Metoprolol succinate significantly lowers blood pressure in the upright, supine, and exercise positions, with effects lasting for more than 24 hours. Lowering blood pressure can reduce fatal and nonfatal cardiovascular events, primarily stroke or myocardial infarction. For angina, take 95-190 mg once daily. Nitrates can be used in combination or the dose increased as needed. Long-term use can reduce the frequency of angina attacks and improve myocardial tolerance. In patients after a myocardial infarction, metoprolol can reduce the risk of subsequent myocardial infarction and cardiac death, especially sudden death after a myocardial infarction. In patients with stable heart failure, it can be combined with angiotensin-converting enzyme inhibitors, diuretics, and possibly digitalis. Patients have stable chronic heart failure, have not experienced an acute heart failure episode in at least the past six weeks, and have not had their basic treatment changed in at least the past two weeks. Studies have shown that metoprolol succinate increases survival and reduces hospitalizations in patients with stable heart failure. Long-term treatment improves overall symptoms (New York Heart Association class and Global Assessment of Treatment score). Treatment of heart failure with beta-blockers can sometimes cause a temporary worsening of symptoms. In some cases, treatment can be continued or the dose reduced, while in others, discontinuation may be necessary. For patients with severe heart failure (NYHA IV), the decision to initiate treatment with metoprolol succinate extended-release tablets should only be made by physicians specifically trained in the treatment of heart failure. Dosage for patients with stable heart failure class II: The recommended starting dose is 23.75 mg once daily within the first two weeks of treatment. After two weeks, the dose can be increased to 47.5 mg once daily. Thereafter, the dose can be doubled every two weeks. The target dose for long-term treatment is 190 mg once daily. Dosage for patients with stable heart failure class III-IV: The recommended starting dose is 11.875 mg (half a 23.75 mg tablet) once daily. The dose should be individualized, and patients should be closely observed during dose increases, as heart failure symptoms may worsen in some patients. After one to two weeks, the dose can be increased to 23.75 mg once daily. After an additional two weeks, the dose can be increased to 47.5 mg once daily. For patients who can tolerate higher doses, the dose can be doubled every two weeks to a maximum of 190 mg once daily. Patients with hypotension and/or bradycardia may need to have their concomitant medications or the dose of this medication reduced. Initial hypotension does not necessarily mean that the patient will not tolerate this medication in the long term, but the dose should be increased only after the patient's condition has stabilized. Other precautions include the need for increased monitoring of renal function. Renal Impairment: Renal function has no significant effect on clearance, so no dose adjustment is required in patients with renal impairment. Hepatic Impairment: For patients with hepatic impairment, consider starting metoprolol therapy at a lower dose than recommended for the specified indication and gradually increase the dose to achieve optimal therapeutic status while closely monitoring the patient for adverse events. The dose of metoprolol succinate used in patients with cirrhosis is generally the same as that used in patients with normal hepatic function. Dose reduction should only be considered in patients with very severe hepatic impairment (such as those undergoing bypass surgery).
Adverse Reactions
See package insert for details.
Contraindications: Cardiogenic shock. Sick sinus syndrome (without permanent pacemaker protection). Second- and third-degree atrioventricular block. Patients with unstable, decompensated heart failure (pulmonary edema, hypoperfusion, or hypotension), patients receiving continuous or intermittent inotropic therapy with beta-agonists. Symptomatic bradycardia or hypotension. This product should not be administered to patients with suspected acute myocardial infarction who have a heart rate <45 beats/min, a P-Q interval >0.24 seconds, or a systolic blood pressure <100 mmHg. Patients with heart failure indications whose supine systolic blood pressure is consistently below 100 mmHg should have their suitability for this product reassessed before initiating treatment. Patients with severe peripheral vascular disease who are at risk of gangrene. Patients with hypersensitivity to any component of this product or other beta-blockers.
