Hypetor

Each film-coated tablet contains: Metoprolol tartrate 50 mg or 100 mg.
Metoprolol is a selective β₁-adrenergic antagonist. It inhibits the inotropic and chronotropic cardiac responses to isoproterenol. It is 1/50^th as potent as propranolol in inhibiting the vasodilator response to isoproterenol; however, it is long acting. It is absorbed well when given orally.

Pharmacology: Pharmacokinetics: Metoprolol is readily and completely absorbed from the gastro-intestinal tract but is subject to considerable first-pass metabolism. Peak plasma concentrations occur about 1.5 hours after a single oral dose. Peak plasma-metoprolol concentrations at steady state with usual doses have been reported as 20 to 340 ng per mL. It is moderately lipid-soluble. Metoprolol is widely distributed, it crosses the blood-brain barrier, the placenta, and is distributed in breast milk. It is slightly bound to plasma protein, it is extensively metabolized in the liver by oxidative deamination-O-dealkylation followed by oxidation and aliphatic hydroxylation. The metabolites are excreted in the urine together with only small amounts of unchanged metoprolol.
The rate of hydroxylation to alpha-hydroxymetoprolol is reported to be determined by genetic polymorphism; the half-life of metoprolol in fast hydroxylators is stated to be 3-4 hours, whereas in poor hydroxylators it is about 7 hours. Metoprolol is removed by dialysis.

Metoprolol is used in the management of hypertension, cardiac arrhythmias, angina pectoris, post myocardial infarction, prophylaxis of migraine and hyperthyroidism.

Hypertension, initially 100 mg daily increased if necessary to 200 mg daily in 1-2 divided doses; max. 400 mg daily (but high doses rarely necessary).
Angina, 50-100 mg 2-3 times daily.
Arrhythmias, usually 50 mg 2-3 times daily; up to 300 mg daily in divided doses if necessary.
Migraine prophylaxis, 100 mg-200 mg daily in divided doses.
Hyperthyroidism (adjunct), 50 mg 4 times daily or as prescribed by the physician.

Metoprolol should not be given to patients with heart failure unless it is controlled. Other contraindications include metabolic acidosis, sinus bradycardia or partial heart block.

Metoprolol should not be given to patients with bronchospasm or asthma or to those with history of obstructive airways disease.

Tiredness, dizziness, gastrointestinal symptoms and sleep disturbances.

Concurrent administration of metoprolol and insulin or oral hypoglycemic agents, their effect may be intensified. The symptoms of reduced blood sugar concentration in particular, accelerated pulse is masked or moderated. Regular blood sugar checks are therefore necessary. Metoprolol can intensify the effect of currently administered antihypertensive medications (particular caution is advised with prazosin). With concurrent administration of nitroglycerine or nifedipine-type calcium antagonist, a stronger drop in blood pressure may occur. With concurrent administration of Verapamil or diltiazem-type calcium antagonists or other anti-arrhythmic agents, careful monitoring of the patient is indicated, as fall in blood pressure, slowing the pulse rate or other cardiac irregularities may occur. During therapy of metoprolol, the IV administration of calcium antagonists or other anti-arrhythmic agents should be avoided. With concurrent administration of adrenaline or other substances with symphathomimetic action (eg. contained in cough mixtures nasal and eye drops), cardioselective β-blockers in therapeutic doses result in lower hypertensive reactions than non-selective β-blockers. With concurrent administration of metoprolol and reserpine, alpha-methyldopa, clonidine guanfacine or cardiac glycosides, there may be stronger drop in cardiac frequency or a delay in stimulus conduction in the heart.
With concurrent therapy with clonidine, clonidine may not be discontinued until several days after the discontinuation of the administration of metoprolol. Rifampicin lowers while cimetidine increases the plasma concentration of metoprolol. Indomethacin may reduce the hypotensive effect of metoprolol. The elimination of other medications may be reduced by metoprolol (eg. lidocaine). The sedative effects of metoprolol and alcohol may be reciprocally intensified. The effects of metoprolol and an anesthetic in reducing the force of myocardial contraction may be compounded. For this reason, the anesthetist should be notified of therapy with metoprolol.

Store at temperatures not exceeding 30°C.

Beta-Blockers

C07AB02 - metoprolol ; Belongs to the class of selective beta-blocking agents. Used in the treatment of cardiovascular diseases.

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