What medications are contraindicated in patients with asthma?

Medications Contraindicated in Asthma

Non-selective beta-blockers are absolutely contraindicated in asthma patients and should never be prescribed, while sedatives are strictly prohibited during acute exacerbations, and NSAIDs should be avoided in patients with aspirin-exacerbated respiratory disease. 1, 2, 3

Absolute Contraindications

Beta-Blockers

Non-selective beta-blockers (propranolol, timolol, nadolol) are explicitly contraindicated in bronchial asthma and can precipitate severe, potentially fatal bronchospasm even at low doses, including topical ophthalmic preparations. 1, 4, 5

• Non-selective agents block both β1 and β2 receptors, causing direct bronchoconstriction and completely blocking the rescue effect of β2-agonist medications like albuterol. 6, 7
• Even "mild" asthmatics can experience severe bronchoconstriction from non-selective beta-blockers, and the severity of response is unpredictable. 5
• Timolol eye drops for glaucoma have caused fatal asthma exacerbations despite minimal systemic absorption. 5

Cardioselective beta-blockers (metoprolol, atenolol, bisoprolol) carry significantly less risk but are not completely safe. 4, 7

• Acute exposure to selective beta-blockers causes a mean FEV1 decline of 6.9%, with one in eight patients experiencing a ≥20% fall in FEV1. 7
• They attenuate β2-agonist rescue response by approximately 10%, compared to 20% attenuation with non-selective agents. 7
• If cardioselective beta-blockers must be used for compelling indications (post-MI, heart failure), use the lowest effective dose and monitor closely, but this should only occur when no acceptable alternatives exist. 6, 4

Sedatives and CNS Depressants

Any sedation is absolutely contraindicated in patients with acute severe asthma or during exacerbations. 2, 8, 9, 10

• Sedatives worsen respiratory depression and can precipitate respiratory failure in patients with compromised respiratory function. 2, 8
• This prohibition applies to all sedating medications including benzodiazepines, barbiturates, and sedating antipsychotics like quetiapine. 10
• Topiramate should be avoided in patients with uncontrolled or severe asthma due to its sedating effects and cognitive impairment, though it may be cautiously considered in well-controlled asthma. 8

Do not prescribe sedatives when any of these features are present: 2, 8, 10

• Respiratory rate >25 breaths/min
• Peak expiratory flow <50% predicted
• Inability to complete sentences in one breath
• Life-threatening features (PEF <33%, silent chest, exhaustion, confusion, hypercapnia)

NSAIDs in Aspirin-Exacerbated Respiratory Disease

Ibuprofen and other NSAIDs are contraindicated in patients with a history of asthma, urticaria, or allergic reactions after taking aspirin or NSAIDs. 3

• This applies to approximately 5-10% of adult asthmatics who have aspirin-exacerbated respiratory disease (AERD). 3
• Severe, rarely fatal anaphylactic-like reactions have been reported in such patients. 3
• Cross-reactivity occurs with all COX-1 inhibiting NSAIDs including ibuprofen, naproxen, ketorolac, and indomethacin. 3

Relative Contraindications and Cautions

Allergen Immunotherapy

Patients with uncontrolled or severe asthma should not receive allergen immunotherapy (subcutaneous or sublingual) due to increased risk of severe systemic reactions and fatal anaphylaxis. 2

• Four of seven fatalities from subcutaneous immunotherapy (2013-2017) occurred in asthmatic patients, with at least two having severe asthma. 2
• Immunotherapy should be postponed until asthma is well-controlled with stable lung function and minimal symptoms. 2
• Withhold scheduled immunotherapy injections if asthma symptoms have worsened since the last visit. 2

Medications Requiring Caution with Epinephrine

Patients unable to tolerate injectable epinephrine should not receive allergen immunotherapy, as epinephrine is first-line treatment for anaphylaxis. 2

• Use extreme caution in patients with hypersensitivity to sympathomimetic drugs, closed-angle glaucoma, severe hypertension, angina, or tachycardia. 2
• These patients require consultation with their cardiologist or other specialist before initiating immunotherapy. 2

Drug Interactions Requiring Monitoring

Monoamine oxidase inhibitors (MAOIs) and tricyclic antidepressants potentiate the cardiovascular effects of albuterol and should be used with extreme caution. 6

• Avoid concurrent use or use within 2 weeks of discontinuing MAOIs or tricyclics. 6
• If combination is unavoidable, monitor closely for tachycardia, hypertension, and arrhythmias. 6

Non-potassium-sparing diuretics (loop and thiazide diuretics) can acutely worsen hypokalemia caused by β2-agonists, especially when recommended doses are exceeded. 6

Medications to Avoid in Specific Clinical Scenarios

During Acute Exacerbations

Antibiotics should not be prescribed unless bacterial infection is clearly documented (consolidation on chest X-ray, purulent sputum with fever). 2, 9

• Upper respiratory infections triggering asthma are typically viral, not bacterial. 9
• Routine antibiotic use provides no benefit and contributes to resistance. 2, 9

Percussive chest physiotherapy is unnecessary and should be avoided during acute exacerbations. 2, 9

Alternative Antihypertensive Options

When treating hypertension in asthmatic patients, prefer calcium channel blockers, ACE inhibitors (with caution), or diuretics over beta-blockers. 11

• Calcium channel blockers have mild bronchodilating effects and no adverse airway effects. 11
• ACE inhibitors may induce cough and bronchial hyperresponsiveness in some patients due to bradykinin accumulation, but are generally safer than beta-blockers. 11

Common Pitfalls to Avoid

• Do not assume cardioselective beta-blockers are completely safe – they still carry risk and should only be used when absolutely necessary with close monitoring. 4, 7
• Do not overlook topical beta-blockers – ophthalmic timolol for glaucoma can cause fatal bronchospasm. 5
• Do not prescribe sedatives for anxiety in patients with poorly controlled asthma – address asthma control first. 8, 10
• Do not assume all asthmatics react to NSAIDs – only those with documented aspirin sensitivity require NSAID avoidance. 3
• Do not start immunotherapy during pregnancy or in patients with recent asthma exacerbations – ensure stability first. 2