Posology : מינונים

4.2   Posology and method of administration

Posology
Labetalol for injection is intended for intravenous use in hospitalised patients.

It is desirable to monitor the blood pressure and heart rate after injection and during infusion.
In most patients, there is a small decrease in the heart rate; severe bradycardia is unusual but may be controlled by injecting atropine 1 to 2 mg intravenously. Respiratory function should be observed particularly in patients with any known impairment.

Once the blood pressure has been adequately reduced by bolus injection or infusion, maintenance therapy with labetalol Tablets should be substituted with a starting dose of 100 mg twice daily.

Labetalol Injection has been administered to patients with uncontrolled hypertension already receiving other hypotensive agents, including beta-blocking drugs, without adverse effects.



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•    Adults:
SEVERE HYPERTENSION

Bolus Injection:

If it is essential to reduce the blood pressure quickly a dose of 50 mg should be given by intravenous injection (over a period of at least one minute) and, if necessary, repeated at five minute intervals until a satisfactory response occurs. The total dose should not exceed 200 mg.
The maximum effect usually occurs within 5 minutes and the duration of action is usually about 6 hours but may be as long as 18 hours.

Intravenous Infusion:

A 1 mg/ml solution of labetalol should be used, i.e. the contents of two ampoules (200mg) diluted to 200 ml with Sodium Chloride and Dextrose Injection BP or 5% Dextrose Intravenous Infusion BP.

HYPERTENSION DUE TO OTHER CAUSES

Infuse at a rate of about 2 mg/min until a satisfactory response is obtained, then stop infusion.
The effective dose is usually 50-200 mg but larger doses may be needed, especially in patients with phaeochromocytoma. The rate of infusion may be adjusted according to the response at the discretion of the physician.

•         Children:

Safety and efficacy in children have not been established.

Method of administration
Patients must always be administered the medicinal product when lying on their back or left side.
Avoid moving the patient to an upright position within 3 hours after intravenous administration of labetalol, as severe postural hypotension may occur.