|Trade names||Alupent, others|
|Other names||Metaproterenol (USAN US)|
|Drug class||β2 adrenergic receptor agonist|
|Main uses||Asthma, COPD|
|Side effects||Anxiety, tremor, headache, palpitations, trouble sleeping, diarrhea, itchiness|
|Inhalation (MDI) and tablets|
|Bioavailability||3% inhaled, 40% by mouth|
|Metabolism||Gastrointestinal and liver|
|Elimination half-life||6 hours|
|Chemical and physical data|
|Molar mass||211.261 g·mol−1|
|3D model (JSmol)|
|Solubility in water||9.7 mg/mL (20 °C)|
Orciprenaline, also known as metaproterenol, is medication used to treat asthma and COPD. It is taken by mouth or inhaled. The medications salbutamol or terbutaline are preferred as they are more effective with less side effects.
Common side effects include anxiety, tremor, headache, palpitations, trouble sleeping, diarrhea, and itchiness. Other side effects may include low potassium and bronchospasm. It is a β2 adrenergic receptor agonist that relaxes smooth muscle in the airways.
Orciprenaline was approved for medical use in the United States in 1973. In the United States 90 tablets of 20 mg costs about 54 USD as of 2021. It was withdrawn from the market in the United Kingdom in 2010.
By mouth it may be used at a dose of 20 mg three to four times per day.
- increased difficulty breathing
- rapid or increased heart rate
- irregular heartbeat
- chest pain or discomfort
Mechanism of action
Orciprenaline is a moderately selective β2 adrenergic receptor agonist that stimulates receptors of the smooth muscle in the lungs, uterus, and vasculature supplying skeletal muscle, with minimal or no effect on α adrenergic receptors. The pharmacologic effects of β adrenergic agonist drugs, such as orciprenaline, are at least in part attributable to stimulation through β adrenergic receptors of intracellular adenylyl cyclase, the enzyme which catalyzes the conversion of ATP to cAMP. Increased cAMP levels are associated with relaxation of bronchial smooth muscle and inhibition of release of mediators of immediate hypersensitivity from many cells, especially from mast cells.
Society and culture
- "Metaproterenol Monograph for Professionals". Drugs.com. Archived from the original on 25 January 2021. Retrieved 16 November 2021.
- "Orciprenaline sulphate (Alupent): reminder of withdrawal from the market". GOV.UK. Archived from the original on 19 July 2017. Retrieved 17 November 2021.
- "Metaproterenol Prices, Coupons & Savings Tips - GoodRx". GoodRx. Archived from the original on 9 August 2021. Retrieved 17 November 2021.