International Nonproprietary Names (INNs) in main languages (French, Latin, Russian, and Spanish):
Pharmacopoeias. In Europe, Japan, and US.
European Pharmacopoeia, 6th ed. (Orciprenaline Sulphate). A white, slightly hygroscopic, crystalline powder. Freely soluble in water slightly soluble in alcohol practically insoluble in dichloromethane. A 10% solution in water has a pH of 4.0 to 5.5. Store in airtight containers. Protect from light.
The United States Pharmacopeia 31, 2008 (Metaproterenol Sulfate). A white to off-white crystalline powder. Freely soluble in water. A 10% solution in water has a pH of 4.0 to 5.5. Store in airtight containers. Protect from light.
Adverse Effects and Precautions
As for Salbutamol. Adverse effects are more common because of the non-selective beta agonist effect of orciprenaline. For the adverse effects and precautions pertaining to non-selective beta agonists see under Sympathomimetics.
As for Salbutamol.
After oral doses orciprenaline is absorbed from the gastrointestinal 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 sulfate is a direct-acting sympathomimetic with mainly beta-adrenoceptor stimulant activity. It has actions and uses similar to those of salbutamol but is less selective for beta2 receptors.
Orciprenaline sulfate is used as a bronchodilator in the management of reversible airways obstruction, as in asthma and in some patients with chronic obstructive pulmonary disease. However, more selective beta2 agonists such as salbutamol or terbutaline are now preferred. On inhalation, the onset of action is usually within 30 minutes and can last from 1 to 5 hours.
A typical adult dose for the relief of acute bronchospasm has been 1 or 2 inhalations of orciprenaline sulfate 750 micrograms from a metered-dose aerosol, repeated as needed up to a maximum of 12 inhalations (9 mg) in 24 hours. In patients with asthma, ‘as-required’ beta agonist therapy is preferable to regular use. An increased need for, or decreased duration of effect of, orciprenaline indicates deterioration of asthma control and the need for review of therapy.
Orciprenaline sulfate has also been inhaled in 5% solution from a hand nebuliser, the usual adult dose being 10 inhalations. If the solution is used with any other nebulising device such as an intermittent positive-pressure breathing (IPPB) apparatus the adult dose is 0.2 to 0.3 mL of a 5% solution diluted up to about 2.5 mL with physiological saline (i.e. dilution to a 0.4 to 0.6% solution) given not more often than every 4 hours. Unit-dose vials containing a prediluted solution of orciprenaline sulfate 0.4 and 0.6% are also available for nebulisation by an IPPB device. In the chronic management of reversible airways obstruction, orciprenaline sulfate has been given orally in a usual adult dose of 20 mg three or four times daily.
Orciprenaline sulfate has also been used similarly to isoprenaline for its cardiovascular effects in the treatment of bradycardia of various types, notably in AV heart block and sinus bradycardia. In such cases oral doses of up to 240 mg daily in divided doses, or 250 to 500 micrograms by slow intravenous injection have been given orciprenaline sulfate may also be given by intravenous infusion, or intramuscular or subcutaneous injection. For doses of orciprenaline used in children, see Administration in Children, below.
Administration in children. Although more selective beta agonists are generally preferred, in some countries orciprenaline sulfate is licensed for use in children via a metered-dose inhaler in similar doses to adults in the USA, use is not recommended under 12 years of age. A metered-dose inhaler was formerly available in the UK and licensed doses in children were:
• under 6 years of age: 1 inhalation of 750 micrograms as necessary doses should not be repeated within 30 minutes. A maximum of 4 inhalations in 24 hours was suggested
• 6 to 12 years of age: 1 or 2 inhalations of 750 micrograms as necessary doses should not be repeated within 30 minutes. A maximum of 8 inhalations in 24 hours was suggested
In patients with asthma, ‘as-required’ beta agonist therapy is preferable to regular use, and chronic oral treatment with orciprenaline would generally be regarded as inappropriate in children. Nonetheless, a syrup is licensed for such use in the UK, licensed oral doses in children being:
• up to 1 year: 5 mg three times daily, increased if necessary to a maximum of 10 mg three times daily
• 1 to 3 years: 5 mg four times daily, increased if necessary to a maximum of 10 mg four times daily
• 3 to 12 years: 10 mg four times daily, increased if necessary to a maximum of 20 mg three times daily
• over 12 years: as for adults (see above)
British Pharmacopoeia 2008: Orciprenaline Tablets
The United States Pharmacopeia 31, 2008: Metaproterenol Sulfate Inhalation Aerosol; Metaproterenol Sulfate Inhalation; Solution Metaproterenol Sulfate Syrup; Metaproterenol Sulfate Tablets.
Chile: Broncodual Compuesto Cloval Compuesto Pulbronc Solvanol Tusabron Vapoflu
Indonesia: Silomat Compositum
Ireland: Alupent Expectorant
Mexico: Bisolpent Ex
South Africa: Adco-Linctopent Benylin Chesty Bisolvon Linctus DA Bronkese Compound Flemeze Silomat DA
Venezuela: Bisolpent Silomat Compositum