Atenolol Tablets 25mg
Out of date information, search anotherSUMMARY OF PRODUCT CHARACTERISTICS
1 NAME OF THE MEDICINAL PRODUCT
Atenolol Tablets 25mg
2. QUALITATIVE AND QUANTITATIVE COMPOSITION
Each tablet contains Atenolol BP 25mg
3. PHARMACEUTICAL FORM
Tablets
4. CLINICAL PARTICULARS
4.1. Therapeutic Indications
1. The management of hypertension
2. The management of angina pectoris
3. The management of cardiac dysrhythmias
4. Myocardial infarction: Early intervention in the acute phase and long-term prophylaxis after recovery from myocardial infarction.
4.2. Posology and Method of Administration
For oral administration Adults
Hypertension:
Most patients respond to 100mg daily given as a single dose. Some patients, however, will respond to 50mg given as a single daily dose. The effect will be fully established after one to two weeks. A further reduction in blood pressure may be achieved by combining Atenolol with other antihypertensive agents. For example, co-administration of Atenolol with a diuretic provides a highly effective and convenient antihypertensive therapy.
Angina:
Most patients with angina pectoris will respond to 100mg given orally once daily or 50mg given twice daily. It is unlikely that additional benefit will be gained by increasing the dose.
Dysrhythmias:
Having controlled the dysrhythmias with intravenous Atenolol a suitable maintenance dosage is 50 mg - 100 mg daily, given as a single dose.
Myocardial infarction:
15 minutes after the administration of the intravenous dose an oral dose of 50 mg may be given provided that no untoward effect occur from the intravenous dose. This should be followed by a further 50mg 12 hours after the intravenous dose and then 12 hours later by 100 mg to be given once daily for up to ten days. If bradycardia and/or hypotension requiring treatment or any other untoward effects occur, Atenolol should be discontinued.
Renal failure:
Atenolol is excreted via the kidneys, dosage adjustment should therefore be considered in patients with severe impairment of renal function. As a guide, for patients with a serum creatinine of 300 - 600 pMol/Litre, the Atenolol oral dose should be 50mg daily or 100mg once every two days, for patients with a serum creatinine of > 600 pMol/Litre, the Atenolol oral dose should be 50mg on alternate days or 100mg once every four days.
Patients on haemodialysis should be given 50mg Atenolol orally following each dialysis. Because of the possibility of marked falls in blood pressure, this should be carried out under hospital supervision.
Elderly
Dosage requirements may be reduced, especially in patients with impaired renal function.
Children
There is no paediatric experience with atenolol and for this reason it is not recommended for use in children.
4.3. Contra-Indications
1. Atenolol is contraindicated in patients with second degree or third degree heart block.
2. Atenolol should not be used in patients with severe bradycardia.
3. Uncontrolled or digitalis/diuretic-refractory heart failure.
4. Atenolol should not be used in patients with cardiogenic shock.
4.4 Special warnings and precautions for use
Sudden withdrawal of Beta-adrenoceptor blocking agents in patients with ischaemic heart disease may result in the appearance of anginal attacks of increased frequency or severity or deterioration in cardiac state. Discontinuation of therapy should be gradual.
Anaesthesia:
Care should be taken when using anaesthetic agents with Atenolol. The anaesthetist should be informed to enable the necessary precautions to be taken.
Atenolol should only be used with caution in patients with controlled congestive cardiac failure or with a family history of asthma. Evidence of development of either condition should be regarded as a signal to discontinue therapy.
The initial treatment of severe malignant hypertension should be so designed as to avoid sudden reduction in diastolic blood pressure with impairment of autoregulatory mechanisms.
Patients with rare hereditary problems of galactose intolerance, the Lapp lactase deficiency or glucose-galactose malabsorption should not take this medicine.
4.5. Interaction with other Medicinal Products and other Forms of Interaction
1. The beta blocker should only be used with great caution in patients who are receiving concomitant myocardial depressants such as chloroform, lignocaine, procainamide, Beta-adrenoceptor stimulants such as isoprenaline, or verapamil or alpha-adrenoceptor stimulants such as noradrenaline, adrenaline (which reverse the hypotensive effects and increase the vasoconstrictor activities).
2. Neurone blocking agents such as Guanethidine, Reserpine, diuretics and other antihypertensive agents, including the vasodilator group, will have an additive effect on the hypotensive action of the drug.
3. The Beta-blocker may mask the symptoms of thyrotoxicosis.
4. Caution should be exercised when transferring patients from Clonidine to beta-adrenoceptor blocking drugs. If the Beta-blocker and Clonidine are given concurrently, the Clonidine should not be discontinued until several days after withdrawal of the Beta-blocker.
4.6. Pregnancy and Lactation
Atenolol should not be given during pregnancy and lactation unless it is considered essential by the physician.
Atenolol has been used effectively under close supervision for the treatment of hypertension associated with pregnancy. Animal studies do not suggest a teratogenic effect with the drug. There is an accumulation of Atenolol in breast milk. However detrimental effects in the baby during breast feeding have not been reported.
4.7. Effects on Ability to Drive and Use Machines
Atenolol may occasionally produce drowsiness, dizziness, light-headedness, blurred vision. Patients should observe caution while driving or performing other tasks requiring alertness.
4.8. Undesirable Effects
Atenolol is generally well-tolerated, side effects associated with it are infrequent and generally mild. Coldness of the extremities and muscular fatigue may occur and, in isolated cases, bradycardia. Sleep disturbances which are associated with some other Beta-blocking preparations are rare.
There have been reports of skin rashes and/or dry eyes associated with the use of Beta-adrenergic blocking drugs. The reported incidence is small and in most cases the symptoms have cleared when treatment was withdrawn. Discontinuance of the drug should be considered if any such reaction is not otherwise explicable. Cessation of therapy with a Beta-blocker should be gradual.
4.9. Overdose
From first principles, excessive bradycardia may be countered by Atropine 1 -2 mg intravenously, and if necessary, this may be followed by a Beta-stimulant, such as Isoprenaline 25 micrograms initially, or Orciprenaline 0.5 mg given by slow intravenous injection. Care must be taken to ensure that the blood pressure does not fall too low if the dose of the Beta-receptor agonist has to be increased. Glucagon has also been reported to be useful as a cardiac stimulant in a dose of 10mg intravenously.
5. PHARMACOLOGICAL PROPERTIES
5.1
Pharmacodynamic Properties
Beta-adrenergic blocking agents (hereafter called Beta-blockers) compete with Beta-adrenergic agonists for available Beta receptor sites. Unselective Beta-blockers inhibit both the Beta1 receptors (located chiefly in cardiac muscle) and Beta2 receptors (located chiefly in the bronchial and vascular musculature)., inhibiting the chronotropic, inotropic and vasodilator responses to Beta-adrenergic stimulation. Atenolol is cardioselective and preferentially inhibits Beta1 adrenoceptors. Beta1 selectivity has been confirmed by the inability of Atenolol to reverse the Beta2 mediated vasodilating effects of Epinephrine or Isoproterenol. This contrasts with the effect of nonselective Beta-blockers which completely reverse the vasodilating effects of Epinephrine.
Atenolol does not have membrane stabilising effects, little direct myocardial depressant activity and little or no intrinsic sympathomimetic activity.
Clinical response to Beta-blockade includes slowing of sinus heart rate, depressed AV conduction, decreased cardiac output at rest and on exercise, reduction of systolic blood pressure on exercise, reduction of both supine and standing blood pressure, inhibition of Isoproterenol-induced tachycardia and reduction of reflex orthostatic tachycardia.
5.2 Pharmacokinetic Properties
Absorption: Atenolol is consistently absorbed when administered orally; with approximately 50 - 60 % of the dose administered being absorbed. After an oral dose of 100mg a mean peak serum level of 880 ng/ml was reached in approximately 3 hours, declining to approximately 63 ng/ml in 24 hours.
Distribution: Atenolol is widely distributed throughout the body, but only a small amount of the drug reaches the brain, Atenolol is not significantly bound to serum proteins.
In pregnancy, atenolol readily crosses the placenta, the umbilical and maternal serum being approximately equal at birth.
Metabolism: Metabolism of atenolol in man is minimal. In animal studies a hydroxylated compound with minor Beta-blocking activity, has been identified as a minor metabolite of Atenolol, but Atenolol does not appear to be metabolised to a significant extent in man.
Excretion: Atenolol is excreted unchanged, mainly through the kidneys. About 40 - 50 % of a single oral dose is excreted in the urine of healthy subjects. The elimination half-life of Atenolol is approximately 6 - 7 hours.
In renal dysfunction, the elimination of Atenolol is closely related to the glomerular filtration rate, although important accumulation probably only occurs if the glomerular filtration is less than 30 ml/minute.
5.3 Pre-clinical Safety Data
No further data is presented given the well-known pre-clinical and clinical profile of Atenolol.
6. PHARMACEUTICAL PARTICULARS
6.1 List of Excipients
Lactose, sodium starch glycollate, magnesium stearate, microcrystalline cellulose, sodium lauryl sulphate, colloidal anhydrous silica, hypromellose, ethylcellulose, diethylphthalate, opaspray orange K-1-2433 which contains E171 and E110.
6.2 Incompatibilities
None known.
6.3 Shelf-Life
Shelf-life unopened container for pack types 1,2 & 3: 5 years. Shelf-life for pack type 4:3 years.
6.4 Special Precautions for Storage
Store below 25 °C.
6.5 Nature and Contents of Container
1. Amber glass bottles with closures of LD-polyethylene.
2. Securitainers
3. Blister packs made of clear PVC plastic foil and aluminium foil, hard tempered, laminated against 30g PVC.
4. Blister packs made of 250pm PVC coated with 60gm2 PVdC and 20pm aluminium lidding foil.
Pack sizes 28, 100, 250
6.6 Instructions for Use, Handling and Disposal
No special Instructions
7. MARKETING AUTHORISATION HOLDER
Sandoz Limited Woolmer Way Bordon Hants GU35 9QE United Kingdom
8. MARKETING AUTHORISATION NUMBER(S)
PL 04416/0278
9. DATE OF FIRST AUTHORISATION / RENEWAL OF THE AUTHORISATION
30 July 1997
10. DATE OF (PARTIAL) REVISION OF THE TEXT
March 2004