Salbutamol vs Fenoterol

Duolin Inhaler contains two bronchodilators: levosalbutamol and ipratropium, which work together to relax the muscles of the airways, reducing bronchospasm (contraction of the airways) and increasing air flow into the lungs.

The synergistic action (interacting to enhance the action of each other) of levosalbutamol and ipratropium in Duolin Inhaler reduces bronchospasm to a greater extent than would be provided by each drug alone, helping to prevent and relieve symptoms of asthma and COPD.

There were studies shown that

• Salbutamol and fenoterol are both effective bronchodilators with no significant difference between them puff per puff as regards potency.
• Fenoterol has a greater peak effect and duration of action than salbutamol, effective duration of action of salbutamol was 3 hours and that of fenoterol 4 hours.
• Fenoterol, however, delivers 200mcg per puff as opposed to 100mcg of salbutamol and fenoterol produced a greater stimulatory effect on heart rate with, in some cases, considerable tachycardia at high doses. An unpleasant taste and tremor were more common following fenoterol.

In conclusion, fenoterol is superior to salbutamol in peak effect and duration of action. However, Salbutamol seems more selective than fenoterol if higher doses of inhaled bronchodilator are required.

References:

• Fenoterol versus salbutamol nebulisation in asthma, Postgraduate Medical Journal (August 1983) 59, 504-505
• A cumulative dose comparison between salbutamol and fenoterol metered dose aerosols in asthmatic patients, Postgraduate Medical Journal (1987) 63, 459-461
• https://www.inhousepharmacy.vu/p-706-duolin-inhaler.aspx