Salbutamol Clinical Use Mode Of Action Adverse Effects

Salbutamol ( INN) or albuterol ( USAN) is a short-acting β₂-adrenergic receptor agonist used for the relief of bronchospasm in conditions such as asthma and COPD. It is marketed by the Allen & Hanbury's respiratory division of GlaxoSmithKline under the trade name Ventolin.

Salbutamol sulfate is usually given by the inhaled route for direct effect on bronchial smooth muscle. This is usually achieved through a metered-dose inhaler (MDI) or nebuliser; but other delivery devices marketed for salbutamol sulfate include the Rotahaler , Diskhaler , and Autohaler . Salbutamol can also be given orally or intravenously.

Ventolin became available in the United Kingdom in 1969 and in the United States in 19801980 is a leap year starting on Tuesday. Events January-February January 1- April 1 National steel strike in United Kingdom January 1 Changes to the Swedish Act of Succession creates Victoria of Sweden, Crown Princess over her younger brother January 5 He.

1 Clinical use

As a β₂-agonist, salbutamol also finds use in obstetricsObstetrics (from the Latin obstare "to stand by") is the surgical specialty dealing with the care of a woman and her offspring during pregnancy, childbirth and the puerperium (the period shortly after birth). Almost all modern obstetricians are also gynae. Intravenous salbutamol can be used as a tocolytic to relax the uterineThe uterus or womb is the major female reproductive organ of most mammals, including humans. One end called the cervix, opens into the vagina, and the wider end, called the body of uterus, is connected on both sides with the Fallopian tubes. It comes in a smooth muscleSmooth muscle is a type of non- striated muscle, found within the " walls" of hollow organs; such as blood vessels, bladders, uteri. gastrointestinal tracts, Smooth muscle is used to move matter withintraction|contraction]]; it generally operates " involu to delay premature labour. Whilst preferred over agents such as atosiban and ritodrine , its role has largely been replaced by the calcium-channel blocker nifedipineNifedipine is a dihydropyridine calcium channel blocker. Its main uses are in angina pectoris (especially Prinzmetal angina) and hypertension, although a large number of other uses have recently sprung up for this agent, such as Raynaud's phenomenon, prem which is more effective, better tolerated and orally effective. (Rossi, 2004)

2 Mode of action

As with other β₂-adrenergic receptor agonists, salbutamol binds to β₂-adrenergic receptors with a higher affinity than β₁-receptors. In the airways, activation of β₂-receptors results in relaxation of bronchial smooth muscle. resulting in a widening of the airway ( bronchodilation ). Inhaled salbutamol sulfate has a rapid onset of action, providing relief within 5-15 minutes of administration.

In tocolysis, the activation of β₂-receptors results in relaxation of uterine smooth muscle, thus delaying labour.

3 Adverse effects

Whilst salbutamol is well-tolerated, particularly when compared with previous therapies such as theophylline, like all medications there exists the potential for adverse drug reactions to occur - especially when in high doses, or when taken orally or intravenously.

Common adverse effects include: tremor, palpitations and headache. (Rossi, 2004)

Infrequent adverse effects include: tachycardia, muscle cramps, agitation, hypokalemia, hyperactivity in children, and insomnia. (Rossi, 2004)

4 References

Rossi S (Ed.) (2004). Australian Medicines Handbook 2004 (AMH). Adelaide: Australian Medicines Handbook. BooksEnthsiast.com.

Beta-adrenergic agonists Phenethylamines Bronchodilators

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Salbutamol
(R,S)-2-(1,1-dimethylethyl)amino- 1-(4-hydroxy-3-hydroxymethylphenyl)ethanol
Empirical formula	C₁₃H₂₂N₁O₅
Molecular weight	239.3
Bioavailability (Oral)	"well absorbed"
Metabolism	hepatic
Elimination half life (Oral/inhaled)	2.7-5 hours
Excretion	renal
Pregnancy category	A ( Australia)