Patient was educated on Salmeterol and its mechanism of action as follows:
- Salmeterol is a long-acting agonist at Beta-2 receptors mainly located in the bronchial smooth muscle of respiratory tract and smooth muscle of blood vessels.
- Salmeterol starts acting in about 30 to 45 minutes and can be effective for 12 to 24 hours.
- Phosphorylation (Addition of phosphate group) of myosin (contractile protein in the smooth muscle) is needed for the smooth muscle to contract. Contraction of the bronchial smooth muscle with narrowing of the airways is the major pathology in individuals with history of asthma and COPD.
- Activation of Beta-2 receptors by Salmeterol inhibits phosphorylation of myosin, and thereby, inhibits the contraction and promotes relaxation of the smooth muscle in the respiratory tract and blood vessels.
- By promoting relaxation of bronchial smooth muscle with dilation of the airways, Salmeterol helps individuals with asthma and COPD, to prevent episodes of acute shortness of breath and dyspnea.
- Due to the slow onset of action, Salmeterol is probably not a good rescue agent during acute exacerbation of shortness of breath and dyspnea. Salmeterol mostly is used for treating serious persistent symptoms of asthma and COPD in individuals who are in continuous distress with repeated exacerbations.
- Relaxation of smooth muscle of blood vessels by Salmeterol can result in dilation of blood vessels and consequently, can contribute towards reduced BP.
