Activation of &beta 2 adrenergic receptors on airway smooth muscle leads to the activation of adenylcyclase and to an increase in the intracellular concentration of cyclic AMP. This increase in cAMP leads to the activation of protein kinase A, which inhibits the phosphorylation of myosin and lowers intracellular ionic calcium concentrations, resulting in relaxation. Levosalbutamol relaxes the smooth muscles of all airways, from the trachea to the terminal bronchioles. Levosalbutamol acts as a functional antagonist to relax the airway irrespective of the spasmogen involved, thus protecting against all bronchoconstrictor.
Dosage & Administration
This Nebuliser Solutionis supplied in unit-dose ampoules and requires no dilution before administration by nebulization.
- Children (6 months-11 years): The recommended dosage is 0.31 mg administered three times a day, by nebulization. Routine dosing should not exceed 0.63 mg three times a day.
- Adults and Adolescents above 12 years old: The recommended starting dosage is 0.63 mg administered three to four times a day, every 6 to 8 hours, by nebulization.
- Patients 12 years of age and older with more severe asthma or patients who do not respond adequately: 0.63 mg of Levosalbutamol Nebuliser Solution may benefit from a dosage of 1.25 mg three times a day.
You should take your Levosalbutamol Inhaler as needed for an asthma attack at any time of day, with or without food, by taking 1-2 puffs up to 4 times daily and no more than 8 puffs in 24 hours. If you are using your Levosalbutamol Inhaler more than 3-4 times a week this may indicate that your asthma is not well controlled and you may need to review your medication. You can also use your Levosalbutamol Inhaler to prevent allergy or exercise induced asthma by taking 2 puffs 15 minutes before exercise or exposure to a known allergen.
Beta-blockers: Beta-adrenergic receptor blocking agents not only block the pulmonary effect of beta-agonists such as Levosalbutamol Nebuliser Solution or Inhaler, but may also produce severe bronchospasm in asthmatic patients. However, under certain circumstances, e.g. prophylaxis after myocardial infarction, there may be no acceptable alternatives to the use of beta-adrenergic blocking agents in patients with asthma. In this setting, cardio selective beta-blockers could be considered with caution.
Diuretics: The ECG changes and/or hypokalemia that may result from the administration of non-potassium sparing diuretics can be acutely worsened by beta-agonists when the recommended dose of the beta-agonist is exceeded.
Digoxin: It is necessary to carefully evaluate the serum digoxin levels in patients who are currently receiving digoxin and Levosalbutamol Nebuliser Solution or Inhaler.
Monoamine Oxidase Inhibitors or Tricyclic Antidepressants: Levosalbutamol Nebuliser Solution or Inhaler should be administered with extreme caution to patients being treated with monoamine oxidase inhibitors or tricyclic antidepressants, or within 2 weeks of discontinuation of such agents.
Pregnancy & Lactation
Lactation: It is not known whether Levosalbutamol is excreted in human milk. Caution should be exercised when Levosalbutamol Nebuliser Solution is administered to a nursing woman.