Betaloc Injection

Betaloc Injection

metoprolol

Manufacturer:

AstraZeneca

Distributor:

Zuellig
/
Four Star
Full Prescribing Info
Contents
Metoprolol tartrate.
Description
Each mL of solution for injection also contains sodium chloride 9 mg and water for injection.
Betaloc solution for injection 1 mg/mL has a pH of approximately 6. Clear colourless solution.
Action
Pharmacology: Pharmacodynamics: IV treatment with metoprolol at myocardial infarction reduces chest pain and lower incidences of atrial fibrillation and atrial flatter. Early administration (within 24 hrs after first symptoms) contributes to limitation of the development and enlargement of the myocardial infarction. Early initiation increases the benefits of treatment.
At paroxysmal atrial tachycardia and atrial fibrillation/flatter, decreased ventricular heart rate is obtained.
Metoprolol is a β1-selective receptor blocker, which means that it affects the β1-receptors of the heart at lower doses than those needed to affect β2-receptors in peripheral vessels and bronchi.
At increasing doses the β1-selectivity may decrease. Metoprolol has no β-stimulating effect and little membrane-stimulating effects. β-blockers have negative inotropic and chronotropic effects.
Metoprolol therapy reduces the effects of catecholamines in association with physical and mental strain, and gives lower heart rate, cardiac output and blood pressure. In stress situations with an increased release of adrenaline from the adrenal glands, metoprolol does not prevent normal physiological vascular dilation. At therapeutic doses, metoprolol has less contractile effect on the bronchial muscles than nonselective β-blockers. This property enables treatment of patients with bronchial asthma or other pronounced obstructive lung diseases with metoprolol in combination with β2-receptor stimulants. Metoprolol influences insulin release and carbohydrate metabolism to a lesser extent than nonselective β-blockers, and it can therefore also be given to patients with diabetes mellitus. Cardiovascular reactions in hypoglycaemia eg, tachycardia, are less influenced by metoprolol, and the return of blood sugar level to normal is fster than for nonselective β-blockers.
Pharmacokinetics: Metoprolol is metabolised in the liver mainly by CYP2D6. Three (3) main metabolites have been identified, though none has any β-blocking effect of clinical significance. The half-life is 3-5 hrs. Metoprolol is excreted to approximately 5% in unchanged form via the kidneys, the remaining dose as metabolites.
Indications/Uses
Supraventricular tachyarrhythmias.
Prophylaxis and treatment of myocardial ischaemia, tachyarrhythmias and pain if suspected or diagnosed myocardial infarction.
Dosage/Direction for Use
Parenteral administration of Betaloc Injection shall be supervised by appropriate personnel, at sites where blood pressure and ECG measurements and resuscitation can be carried out.
Supraventricular Tachyarrhythmia: Initially, 5 mg (=5 mL) is to be given intravenously at 1-2 mg/minute. This dose can be repeated every 5 minute until the desired effect is reached. Usually a total dose of 10-15 mg (=10-15 mL) is sufficient. Recommended maximum intravenous dose: 20 mg (=20 mL).
Prophylaxis and Treatment of Myocardial Ischemia, Tachyarrhythmia and Pain if Suspected or Diagnosed Myocardial Infarction: Acute: Give 5 mg (=5 mL) intravenously. The dose can be repeated every 2 minutes, maximum dose 15 mg (=15 mL). 15 minutes after the last injection, give 50 mg metoprolol tartrate orally every 6 hours for 48 hours. For continued (oral) treatment Betaloc tablets or Betaloc ZOK prolonged release tablets should be given.
Contraindications
Known hypersensitivity to metoprolol tartrate or other β-blockers. Cardiogenic shock. Sick sinus syndrome. AV block. Patients with unstable, uncompensated heart failure (pulmonary oedema, hypoperfusion or hypotension), and patients with continuous or intermittent inotropic therapy acting through β-receptor agonism. Symptomatic bradycardia or hypotension. Metoprolol should not be given to patients with suspected acute myocardial infarction as long as the heart rate is <45 beats/min, the P-Q interval is >0.24 sec or the systolic blood pressure is <100 mmHg. In treatment of supraventricular tachyarrhythmia, Betaloc Injection should not be given IV to patients with a systolic blood pressure <110 mmHg. Serious peripheral vascular disease with gangrene threat.
Special Precautions
Verapamil should not be administered intravenously to patients being treated with β-blockers. When treating patients with suspected or confirmed heart failure the haemodynamic status of the patient should be carefully monitored after each dose. Ongoing, treatment should be interrupted if there is any aggravation of dyspnoea or cold sweating.
Metoprolol may aggravate the symptoms of peripheral arterial circulatory disorders, eg, intermittent claudication. Severely impaired renal function. Serious acute conditions with metabolic acidosis. Combination treatment with digitalis.
Betaloc Injection should not be given to patients with latent or manifest heart insufficiency without concomitant treatment.
In patients with Prinzmetal's angina, the frequency and extent of angina attacks may increase owing to α-receptor-mediated contraction of the coronary vessels. For this reason, nonselective β-blockers must not be used in these patients. β1-selective receptor blockers should be used with caution.
In bronchial asthma or other chronic obstructive lung diseases, adequate bronchodilating therapy should be given concomitantly. The dose of β2-stimulants may need to be increased. If Betaloc Injection is given to patients with phaeochromocytoma, treatment with α-blockers should be considered.
Treatment with metoprolol may interfere with carbohydrate metabolism or mask hypoglycaemia, although the risk is lower than with nonselective β-blockers.
Very rarely, a moderate preexisting AV conduction disorder may become aggravated (possibly leading to AV block).
Treatment with β-blockers may aggravate the treatment of an anaphylactic reaction. If Betaloc is given to a patient with phaeochromocytoma, treatment with an alpha-blocker should be considered.
If withdrawal of Betaloc is necessary, it should, if possible, be done gradually over a period of 2 weeks, otherwise angina pectoris symptoms may be aggravated, with an increased risk of myocardial infarction.
Prior to surgery, the anaesthetist should be informed that the patient is receiving Betaloc. It is recommended that β-blocker treatment is not withdrawn for patients undergoing surgery. Acute initiation of high-dose metoprolol to patients undergoing noncardiac surgery should be avoided, since it has been associated with bradycardia, hypotension and stroke including fatal outcome in patients with cardiovascular risk factors.
The 2nd or 3rd dose should not be given if the heart rate is <40 beats/min, the systolic blood pressure is <90 mmHg and the P-Q time is >0.26 seconds.
Use in pregnancy: Betaloc should not be given during pregnancy and lactation unless it is considered absolutely essential.
β-receptor blockers may cause bradycardia in the foetus and in the newborn infant. This should be taken into account if these drugs are prescribed in the last trimester of pregnancy and in association with delivery.
Betaloc should gradually be withdrawn 48-72 hours before planned childbirth. If this is not possible the newborn infant should be supervised during 48-72 hours postpartum for signs and symptoms of β blockade (eg, heart- and lung complications).
Use in lactation: Metoprolol is concentrated in human breast milk in a quantity that corresponds to approximately 3 times the quantity found in the plasma of the mother. The risk for harmful reactions with respect to the breast-feeding child seems to be low at therapeutic doses of the medicine. The breast-fed child should however be observed regarding signs of β blockade.
Use In Pregnancy & Lactation
Use in pregnancy: Betaloc should not be given during pregnancy and lactation unless it is considered absolutely essential.
β-receptor blockers may cause bradycardia in the foetus and in the newborn infant. This should be taken into account if these drugs are prescribed in the last trimester of pregnancy and in association with delivery.
Betaloc should gradually be withdrawn 48-72 hours before planned childbirth. If this is not possible the newborn infant should be supervised during 48-72 hours postpartum for signs and symptoms of β blockade (eg, heart- and lung complications).
Use in lactation: Metoprolol is concentrated in human breast milk in a quantity that corresponds to approximately 3 times the quantity found in the plasma of the mother. The risk for harmful reactions with respect to the breast-feeding child seems to be low at therapeutic doses of the medicine. The breast-fed child should however be observed regarding signs of β blockade.
Adverse Reactions
Adverse reactions occur in approximately 10% of the patients and are usually dose-related.
Adverse reactions related to all use of metoprolol are shown below according to system organ class and frequency. The following definitions of frequencies are used: Very common (≥1/10), common (≥1/100 and <1/10), uncommon (≥1/1000 and<1/100), rare (≥1/10000, <1/1000) and very rare (<1/10000), not known (cannot be estimated from the available data).
Cardiac Disorders: Common: Bradycardia, palpitations. Uncommon: Chest pain, transient aggravation of heart failure, cardiogenic shock in patients with acute myocardial infarction. Rare: Prolonged AV conduction time, cardiac arrhythmias.
Blood and Lymphatic System Disorders: Rare: Thrombocytopenia.
Nervous System Disorders: Common: Headache, dizziness. Uncommon: Paraesthesiae.
Eye Disorders: Rare: Visual disturbances, dry and/or irritated eyes. Not Known: Conjunctivitis.
Ear and Labyrinth Disorders: Rare: Tinnitus.
Respiratory, Thoracic and Mediastinal Disorders: Common: Shortness of breath upon exercise. Uncommon: Bronchospasm in patients with bronchial asthma or asthmatic problems. Not Known: Rhinitis.
Gastrointestinal Disorders: Common: Abdominal pain, nausea, vomiting, diarrhoea, constipation. Rare: Taste disturbances. Not Known: Dry mouth.
Skin and Subcutaneous Tissue Disorders: Uncommon: Hypersensitivity reactions on the skin. Rare: Aggravated psoriasis, photosensitivity reactions, hyperhidrosis, hair loss.
Musculoskeletal and Connective Tissue Disorders: Not Known: Muscular cramps, arthralgia.
Vascular Disorders: Common: Peripheral coldness in extremities. Rare: Syncope. Not Known: Gangrene in patients with severe peripheral vascular disorders.
General Disorders and Administration Site Conditions: Very Common: Fatigue. Uncommon: Oedema, weight gain.
Hepatobiliary Disorders: Rare: Elevated transaminases. Not Known: Hepatitis.
Reproductive System and Breast Disorders: Rare: Reversible libido dysfunction.
Psychiatric Disorders: Uncommon: Depression, nightmares, sleep disturbances. Rare: Memory impairment, confusion, nervousness, anxiety, hallucinations. Not Known: Impaired concentration ability.
Drug Interactions
Metoprolol is a CYP2D6-substrate. Drugs that inhibit CYP2D6 may have an effect on the plasma concentration of metoprolol. Examples of drugs that inhibit CYP2D6 are quinidine, terbinafine, paroxetine, fluoxetine, sertraline, celecoxib, propafenon and diphenhydramine. When treatment with these drugs are initiated the dose of Betaloc might have to be reduced for patients treated with Betaloc.
The following combinations with Betaloc Injection should be avoided: Barbituric acid derivatives, propafenone and verapamil.
The following combinations with Betaloc Injection may require a dose adjustment: Class I antiarrhythmic drugs, amiodarone, diphenhydramine, digitalis glycosides, diltiazem, epinephrine, phenylpropanolamine, nonsteroidal anti-inflammatory/antirheumatic drugs (NSAIDs), quinidine, clonidine and rifampicin.
Patients receiving concomitant treatment with other β-blockers (eg, eye drops) or MAO-inhibitors should be kept under close surveillance. In patients on β-receptor blocker therapy, inhalation anaesthetics enhance the cardiodepressant effect. The dosages of oral antidiabetics may have to be readjusted in patients taking β-blockers. The plasma concentration of metoprolol may increase when cimetidine or hydralazine are administered simultaneously.
Incompatibilities: Macrodex is not suitable for mixing with Betaloc Injection.
Compatibility: Betaloc solution for injection 1 mg/mL equivalent to up to metoprolol 40 mg may be added to 1000 mL of the following solutions for infusion: Sodium chloride 0.9%, mannitol 150 mg/mL, glucose 100 mg/mL, glucose 50 mg/mL, fructose 200 mg/mL, invertose 100 mg/mL, Ringer, Ringer glucose, Ringer acetate.
Caution For Usage
Stability: Diluted solution for injection should be used within 12 hrs.
Storage
Do not store above 25°C.
MIMS Class
ATC Classification
C07AB02 - metoprolol ; Belongs to the class of selective beta-blocking agents. Used in the treatment of cardiovascular diseases.
Presentation/Packing
Amp 1 mg/mL x 5 mL x 5's.
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