What are the indications and absolute contraindications for Salbutamol (albuterol) administered orally (PO)?

Indications and Contraindications for Oral Salbutamol (Albuterol)

Oral salbutamol should be considered as second-line treatment to inhaled bronchodilators for patients with asthma or COPD who cannot effectively use inhaled medications. 1

Indications for Oral Salbutamol

Primary Indications:

• Alternative therapy for patients who cannot use inhalers effectively 1
• Chronic persistent asthma when inhaled therapy has failed after formal evaluation 1
• Management of COPD when inhaled therapy is inadequate 1
• Prophylaxis against antigen-induced asthma (requires higher doses - 8mg slow-release preparation) 2

Patient-Specific Indications:

• Elderly patients with coordination difficulties using inhalers
• Patients with cognitive impairments affecting inhaler technique
• Children who cannot master proper inhaler technique
• Patients with physical limitations preventing effective inhaler use

Absolute Contraindications

• Hypersensitivity to salbutamol or any component of the formulation 3
• Tachyarrhythmias requiring treatment
• Severe cardiac disease where increased heart rate would be detrimental

Relative Contraindications/Cautions

• Cardiovascular disorders: May precipitate angina in susceptible patients 1
• Diabetes mellitus: Can affect glucose metabolism
• Hyperthyroidism: May potentiate effects of beta-agonists
• Concurrent use of non-selective beta-blockers: Antagonizes effects of salbutamol
• Hypokalemia: Beta-agonists can decrease serum potassium

Dosing Considerations

Standard Dosing:

• For adults requiring oral therapy: 4mg standard release or 8mg slow-release preparation 2
• Higher doses (8mg SR) may be needed for prophylaxis against antigen-induced asthma 2

Administration Algorithm:

1. First choice: Always attempt inhaled route first (200-400μg salbutamol via MDI) 1
2. If inhaler technique inadequate: Consider spacer device before switching to oral route 1
3. If inhaled route still not feasible: Use oral salbutamol at appropriate dose
4. If response inadequate: Consider combination with other bronchodilators 1

Efficacy Considerations

• Oral salbutamol has slower onset of action compared to inhaled route 4
• Bronchodilator effect is significantly less than inhaled salbutamol at standard doses 4
• Higher blood levels are required for oral route to achieve comparable effects 2
• May have added benefit when combined with inhaled therapy in some patients 4

Important Clinical Pearls

• Always assess inhaler technique before switching to oral therapy 1
• The oral route has more systemic side effects than inhaled administration 5
• Regular nebulized bronchodilator treatment should only be undertaken after formal evaluation of its benefit 1
• When using oral salbutamol for prophylaxis, higher doses (8mg SR) are needed compared to standard treatment doses 2
• Monitor for cardiovascular effects, especially in elderly patients 1

Monitoring

• Monitor heart rate and blood pressure when initiating therapy
• Watch for tremor, nervousness, and other systemic beta-agonist effects
• In long-term use, monitor for tachyphylaxis (diminishing response over time)
• Assess therapeutic response using objective measures (PEF, spirometry) when possible

Remember that while oral salbutamol is an option for patients who cannot use inhalers effectively, the inhaled route remains superior for delivering medication directly to the airways with fewer systemic effects 4.