respiratory beta2_agonist saba bronchodilator

Albuterol is the first-line rescue bronchodilator for acute bronchospasm in asthma and COPD.

It rapidly relaxes airway smooth muscle but does NOT treat inflammation.

β2 receptor stimulation → ↑ cAMP → bronchial smooth muscle relaxation

Additional effects:

• ↓ mast cell mediator release
• ↑ mucociliary clearance
• Drives potassium into cells (↓ serum K⁺)

• Acute asthma symptoms
• Exercise-induced bronchospasm prevention
• COPD rescue therapy
• Hyperkalemia (temporary potassium shift)

MDI: 1–2 puffs every 4–6 hours PRN Nebulizer: 2.5 mg every 4–6 hours PRN Exercise prevention: 2 puffs 15 minutes before activity

Frequent use (>2 days/week) → indicates uncontrolled asthma

Dose dependent.

• Severe tachyarrhythmias
• Hyperthyroidism
• Caution in ischemic heart disease

Not a steroid — safe in pregnancy and pediatrics.

• First drug given in asthma exacerbation
• Spacer improves lung deposition significantly
• Nebulizer does NOT deliver more drug — only easier for severe distress
• Causes temporary improvement in hyperkalemia

• Symptom frequency
• Rescue inhaler use per week
• Heart rate in high-dose therapy
• Potassium (continuous nebs)

• Levalbuterol
• Formoterol
• Inhaled Corticosteroids