Following an allergic reaction, patient may suffer with respiratory symptoms such as  tightness of chest and wheezing. These are the common symptoms in asthma too, occured due to constriction of bronchial smooth muslces and bronchodilators such as salbutamol inhaler  are used to relief these symptoms. A bronchodilator is an  inhaled drug, which control the asthma symptoms by relaxing the smooth muscles in the lungs.inhaler

A short acting bronchodilator provides  quick relief of asthma symptoms and long acting bronchcodilators can provide upto 12 hours of reief from astma symptoms.  The later  is useful for the patinets who  suffer with increased nocturnal symptoms . Bronchodilator are available in syrup and tablet form, however, inhaler is more effective and has quicker response.
A patient with the severe acute respiratory  symptoms may need to be treated with nebulised bronchodilator e,g. salbutamol, using  a nebuliser. A nebuliser  is a small device can covert a small amount of salbutamol solution into  gas form/a mist of salbutamol particles  by means of a compressor. Then it can be inhaled by the patient via a face mask.