Albuterol - Drug Monograph

Introduction

Albuterol (also known as salbutamol outside the United States) is a short-acting β2-adrenergic receptor agonist (SABA) medication primarily used for the treatment and prevention of bronchospasm in patients with reversible obstructive airway diseases. First approved by the FDA in 1981, it remains one of the most widely prescribed bronchodilators worldwide for acute asthma exacerbations and exercise-induced bronchospasm.

Mechanism of Action

Albuterol selectively stimulates β2-adrenergic receptors in bronchial smooth muscle, leading to activation of adenylate cyclase and increased intracellular cyclic AMP (cAMP). This results in relaxation of bronchial smooth muscle, bronchodilation, and reduced airway resistance. At therapeutic doses, albuterol has minimal effects on β1-adrenergic receptors in the heart, though some cardiovascular stimulation may occur at higher doses.

Indications

• Treatment and prevention of bronchospasm in patients with reversible obstructive airway disease (asthma)
• Prevention of exercise-induced bronchospasm
• COPD (chronic obstructive pulmonary disease) management
• Off-label uses may include hyperkalemia treatment and tocolysis

Dosage and Administration

• Adults and children ≥4 years: 1-2 inhalations every 4-6 hours as needed
• Prevention of EIB: 2 inhalations 15-30 minutes before exercise

• Adults: 2.5 mg 3-4 times daily as needed
• Children: 0.63 mg to 2.5 mg 3-4 times daily as needed (age-dependent dosing)

• Hepatic impairment: No dosage adjustment required
• Renal impairment: Use with caution; no specific dosage recommendation
• Elderly: Start at lower end of dosing range due to increased sensitivity

Pharmacokinetics

Contraindications

• Hypersensitivity to albuterol or any component of the formulation
• History of hypersensitivity reactions to other sympathomimetic amines

Warnings and Precautions

• Paradoxical bronchospasm: May occur with excessive use; discontinue immediately if occurs
• Cardiovascular effects: May cause significant blood pressure elevation, tachycardia, and palpitations
• Hypokalemia: May occur due to intracellular shifting of potassium
• Diabetes mellitus: May transiently increase blood glucose levels
• Seizure disorders: May be exacerbated by hypokalemia or other metabolic effects
• Thyrotoxicosis: May aggravate symptoms of hyperthyroidism

Drug Interactions

• Beta-blockers: May antagonize bronchodilator effects (non-selective beta-blockers)
• Diuretics: Increased risk of hypokalemia when used concurrently
• Digoxin: Risk of hypokalemia may increase digoxin toxicity
• MAO inhibitors/Tricyclic antidepressants: May potentiate cardiovascular effects
• Other sympathomimetics: Additive cardiovascular and CNS effects

Adverse Effects

• Nervousness
• Tremor
• Headache
• Tachycardia
• Palpitations

• Dizziness
• Throat irritation
• Cough
• Nausea
• Muscle cramps

• Paradoxical bronchospasm
• Angina
• Hypertension/hypotension
• Anaphylaxis
• Hypokalemia

Monitoring Parameters

• Pulmonary function tests (FEV1, peak flow)
• Heart rate and rhythm
• Blood pressure
• Serum potassium levels (with frequent use)
• Blood glucose (in diabetic patients)
• Therapeutic response and symptom control
• Inhaler technique assessment

Patient Education

• Use exactly as prescribed; do not exceed recommended dosage
• Shake inhaler well before each use
• Prime inhaler before first use or if not used for 2 weeks
• Rinse mouth after inhalation to prevent oral candidiasis
• Seek medical attention if symptoms worsen or if needing more frequent doses
• Keep rescue inhaler readily available at all times
• Understand difference between rescue (albuterol) and controller medications
• Report chest pain, rapid heartbeat, or tremors to healthcare provider
• Proper inhaler technique demonstration and regular reassessment

References

1. National Heart, Lung, and Blood Institute. (2020). Expert Panel Report 3: Guidelines for the Diagnosis and Management of Asthma. 2. Global Initiative for Asthma. (2023). GINA Report, Global Strategy for Asthma Management and Prevention. 3. Lexicomp Online®. (2023). Albuterol monograph. Hudson, Ohio: Wolters Kluwer Clinical Drug Information, Inc. 4. Micromedex® Solutions. (2023). Albuterol drug information. Truven Health Analytics, Inc. 5. FDA Prescribing Information: ProAir HFA, Ventolin HFA, Proventil HFA. 6. Barnes PJ. (2017). Theophylline. American Journal of Respiratory and Critical Care Medicine. 7. Johnson M. (1998). The beta-adrenoceptor. American Journal of Respiratory and Critical Care Medicine.