Monograph: |
Orciprenaline Sulphate
A white to off-white, odourless or almost odourless, hygro-
scopic. crystalline powder. Freely soluble in water and in al-
cohol; practically insoluble in dichloromethane and in ether.
A 10% solution in water has a pH of 4.0 to 5.5. Store in air-
tight containers. Protect from light.
Adverse Effects and Precautions
For the adverse effects and precautions pertaining to a non-
selective beta agonist see Isoprenaline Sulphate.
Interactions
As for Isoprenaline Sulphate.
Pharmacokinetics
Following oral administration orciprenaline is absorbed from
the gastro-intestinal tract and undergoes extensive first-pass
metabolism in the liver; about 40% of an oral dose is reported
to reach the circulation unchanged. It is excreted in the urine
primarily as metabolites.
Uses and Administration
Orciprenaline sulphate is a direct-acting sympathomimetic
with predominantly beta-adrenoceptor stimulant activity. It
has actions and uses similar to those of salbutamol
but is less selective for beta-2 adrenergic receptors.
Orciprenaline sulphate is used as a bronchodilator in the man-
agement of reversible airways obstruction, as occurs in asth-
ma and in some patients with chronic obstructive
pulmonary disease . However, more selective beta-2 ag-
onists such as salbutamol or terbutaline are now generally
preferred. Following inhalation, the onset of action is usually
within 5 to 30 minutes and can last up to 6 hours, though there
is wide variation.
A usual adult dose for the relief of bronchospasm is I or 2
inhalations of orciprenaline sulphate 750 ug from a metered-
dose aerosol, repeated if required after not less than 30 min-
utes, up to a maximum of 12 inhalations (9 mg) in 24 hours.
A suggested maximum dose within a 24-hour period for chil-
dren is: under 6 years, up to 4 inhalations: 610 12 years, up to
8 inhalations.
Orciprenaline sulphate has also been inhaled in 5% solution
from a hand nebulizer, the usual adult dose being 10 inhala-
tions. If the solution is used with any other nebulising device
such as an intermittent positive pressure breathing (IPPB) ap-
paratus the adult dose is 0.2 to 0.3 mL of a 5% solution dilut-
ed up to about 2.5 mL with sterile water or physiological
saline (i.e. dilution to a 0.4 to 0.6% solution) administered not
more often than every 4 hours. Unit-dose vials containing a
prediluted solution of orciprenaline sulphate 0.4% and 0.6%
are also available for nebulization by an IPPB device.
In the chronic management of reversible airways obstruction,
orciprenaline sulphate may be given by mouth in a dose of
20 mg four times daily. A suggested dose for children is: up
to I year, 5 to 10 mg three times daily: I to 3 years, 5 to 10 mg
four times daily: 3 to 12 years. 10 mg four times daily to
20 mg three times daily.
Orciprenaline sulphate has also been used for its cardiovascu-
lar effects in the treatment of bradycardia of various types,
notably in AV heart block and sinus bradycardia. In such cas-
es doses of up to 240 mg daily by mouth in divided doses, or
250 to 500 ng by slow intravenous injection have been given;
orciprenaline sulphate may also be given by intravenous infu-
sion, or intramuscular or subcutaneous injection.
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