Levalbuterol

Levosalbutamol

Mechanism :

Activation of beta2-adrenergic receptors on airway smooth muscle leads to the activation of adenyl cyclase and to an increase in the intracellular concentration of cyclic-3', 5'-adenosine monophosphate (cyclic AMP). This increase in cyclic AMP leads to the activation of protein kinase A, which inhibits the phosphorylation of myosin and lowers intracellular ionic calcium concentrations, resulting in relaxation. Levalbuterol relaxes the smooth muscles of all airways, from the trachea to the terminal bronchioles.

Indication :

• Prevention of bronchospasm in reversible obstructive airway disease
• Asthma exacerbation

Contraindications :

Contraindicated in patients with a history of hypersensitivity to levalbuterol HCl or racemic albuterol.

Dosing :

Nebulization: Under 5 years: 0.31-1.25 mg every 4-6 hours as per requirement.

5-12 years: 0.31 mg every 8 hours; Max: 0.63 mg every 8 hours as per requirement.

Above 12 years: 0.63-1.25 mg every 8 hours as per requirement.

Inhalation: Under 4 years: Safety and efficacy not established.

Above 4 years: 90 mcg (2 puffs of metered-dose inhaler) every 4-6 hours as per requirement.

Adverse Effect :

Tremors, nervousness, insomnia, hypertension, angina, vomiting, vertigo, hyperactivity and excitement, unusual taste, drying or irritation of the oropharynx. headache, dizziness, increased appetite, angioedema, urticaria, tachycardia, epistaxis.

Interaction :

Monoamine Oxidase Inhibitors or Tricyclic Antidepressants: 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, because the action of levalbuterol on the vascular system may be potentiated.

Hepatic Dose :