TENORMIN Solution for injection Ref.[6738] Active ingredients: Atenolol

Posology

The dose must always be adjusted to individual requirements of the patients, with the lowest possible starting dosage. The following are guidelines:

Adults

Cardiac arrhythmias

A suitable initial dose of Tenormin is 2.5 mg (5 ml) injected intravenously over a 2.5 minute period (i.e. 1 mg/minute). This may be repeated at 5 minute intervals until a response is observed up to a maximum dosage of 10 mg. If Tenormin is given by infusion, 0.15 mg/kg bodyweight may be administered over a 20 minute period. If required, the injection or infusion may be repeated every 12 hours. Having controlled the arrhythmias with intravenous Tenormin, a suitable oral maintenance dosage is 50 to 100 mg daily (see prescribing information for Tenormin and Tenormin LS tablets).

Myocardial infarction

For patients suitable for treatment with intravenous beta-blockade and presenting within 12 hours of the onset of chest pain, Tenormin 5–10 mg should be given by slow intravenous injection (1 mg/minute) followed by Tenormin 50 mg orally about 15 minutes later, provided no untoward effects have occurred from the intravenous dose. This should be followed by a further 50 mg orally 12 hours after the intravenous dose, and then 12 hours later by 100 mg orally, once daily. If bradycardia and/or hypotension requiring treatment, or any other untoward effects occur, Tenormin should be discontinued

Elderly

Dosage requirements may be reduced, especially in patients with impaired renal function.

Paediatric population

There is no paediatric experience with Tenormin and for this reason it is not recommended for use in children.

Renal impairment

Since Tenormin is excreted via the kidneys, the dosage should be adjusted in cases of severe impairment of renal function.

No significant accumulation of Tenormin occurs in patients who have a creatinine clearance greater than 35 ml/min/1.73 m² (normal range is 100–150 ml/min/1.73 m²).

For patients with a creatinine clearance of 15–35 ml/min/1.73 m² (equivalent to serum creatinine of 300–600 micromol/litre), the oral dose should be 50 mg daily and the intravenous dose should be 10 mg once every two days.

For patients with a creatinine clearance of less than 15 ml/min/1.73 m² (equivalent to serum creatinine of greater than 600 micromol/litre), the oral dose should be 25 mg daily or 50 mg on alternate days and the intravenous dose should be 10 mg once every four days.

Patients on haemodialysis should be given 50 mg orally after each dialysis; this should be done under hospital supervision as marked falls in blood pressure can occur.

Method of administration

Administered by the intravenous route.

The symptoms of overdosage may include bradycardia, hypotension, acute cardiac insufficiency and bronchospasm.

General treatment should include: close supervision; treatment in an intensive care ward; the use of gastric lavage; activated charcoal and a laxative to prevent absorption of any drug still present in the gastrointestinal tract; the use of plasma or plasma substitutes to treat hypotension and shock. The possible uses of haemodialysis or haemoperfusion may be considered.

Excessive bradycardia can be countered with atropine 1–2 mg intravenously and/or a cardiac pacemaker. If necessary, this may be followed by a bolus dose of glucagon 10 mg intravenously. If required, this may be repeated or followed by an intravenous infusion of glucagon 1–10 mg/hour depending on response. If no response to glucagon occurs or if glucagon is unavailable, a beta-adrenoceptor stimulant such as dobutamine 2.5 to 10 micrograms/kg/minute by intravenous infusion may be given. Dobutamine, because of its positive inotropic effect could also be used to treat hypotension and acute cardiac insufficiency. It is likely that these doses would be inadequate to reverse the cardiac effects of beta-blocker blockade if a large overdose has been taken. The dose of dobutamine should therefore be increased if necessary to achieve the required response according to the clinical condition of the patient.

Bronchospasm can usually be reversed by bronchodilators.

Shelf life: 36 months.

Do not store above 25°C. Keep the container in the outer carton.

Glass ampoules.

10 ml ampoules are packed in boxes of 10.

Use as instructed by the prescriber.

Tenormin Injection is compatible with sodium chloride intravenous infusion (0.9 %w/v) and Glucose Intravenous Infusion BP (5 % w/v).