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International generic name
Atenolol
Drug form and composition
Film-coated tablets. One tablet contains 50 mg Atenolol.
Indications
Stable and non-stable angina pectoris, which are due to coronary artery sclerosis;
arterial hypertension of different genesis (including renal hypertension).
Dosage and administration
Usual dosage in patients with angina pectoris and hypertension is 50-100 mg ones
daily, as the effect becomes evident 1-2 weeks after initial dose. In patients with
renal failure the dose should be corrected depending on the creatine clearance.
If the clearance of creatine is 15-35 ml per minute, the dosage of Atenolol should
be 50 mg ones daily; if the clearance is lower than 15 ml per minute, the same dose
should be given each second day.
Contraindications
Second or third degree heart block; heart failure with decompensated hemodynamics;
hypotension in myocardial infarction; cardiogenic shock; sinus node bradicardia
(below 45 beats per minute); hypersensitivity to the preparation. Atenolol mustn’t
be given to children.
Special warnings and precautions
In case of abrupt interruption of medication with Atenolol is possible to appear
“withdrawal syndrome”, manifesting with severely heart disorders. This phenomenon
is explained with a sensibilization of the beta-adrenergic receptors and increased
norepinephrine releasing. For this reason the treatment with the preparation should
be reduced gradually. In patients with bronchial asthma and COPD Atenolol may cause
a bronchial obstruction and provoke an asthmatic attack, which due to blocking of
the beta-adrenergic bronchial dilation. Atenolol should be administered with caution
in patient with diabetes mellitus, as it may mask the tachycardia in case of hypoglycemia.
In impending surgery under general anesthesia the treatment should be stopped 48
hours before operation. In pregnancy and lactation Atenolol is used only in cases
with favourable risk/benefit ratio.
Drug interactions
In concomitant treatment with clonidin, Atenolol is withdrawn several days prior
to clonidin interruption, in order to avoid the clonidin “steal” syndrome. Atenolol
intensifies the hypoglycemia, caused by sulphonylurea preparations, depressing the
contraregulatory mechanisms; enhances the negative chronotropic and dromotropic
effects of the centrally acting antihyprtensive drugs, as reserpin and methyldopa;
accentuates antiarrhythmic capabilities of the calcium channel blocking agents (verapamil,
diltiazem); potentiates action of the nondepolarizing neuromuscular blocking agents.
Concomitant treatment with Atenolol and digitalis glycosides may lead to bradicardia
and heart block, which requires an ECG-monitoring. Cimmetidin elevates the plasma
level of the Atenolol and increases its effects. Concomitant application of NSAID
may reduce the antihypertensive effect of Atenolol, due to suppression of the renal
synthesis of prostaglandines as well as fluid and sodium ions retention.
Adverse reactions
Following adverse reactions may be seen: hypotonia; bradicardia; paresthesies;
cold limbs; exacerbation of the peripheral circulation disturbances; fatigue; dizziness;
headache; nausea and gastrointestinal symptoms; hypersensitivity reactions, particularly
skin manifestations. Rarely may appear heart failure aggravation; AV - block; bronchial
obstruction; depression; hypoglycemia; thrombocytopenia; hyperlipemia.
Pharmacological mechanisms
Atenolol is a selective antagonist of the β1 - receptors, and has no membrane
stabilizing and internal sympathicomimetic action. The basis of its antihypertensive
action is depression of the renal renine secretion. Relive of the angina pectoris
symptoms is due to reduction of the oxygen requirements of the myocardium. Atenolol
reduces the cardiac output and contractility. In therapeutic dose it influences
chronotrope, inotrope and dromotrope effects of the cardiac sympathetic stimulation.
Its effects are better manifested during exercise and elevated sympathetic tone.
Supplied
30 film-coated tablets Atenolol of 50 mg.
Expiry
2 years.
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