What causes seeing stars after coughing, especially in adults with a history of respiratory problems such as asthma, Chronic Obstructive Pulmonary Disease (COPD), pneumonia, hypertension (High Blood Pressure), heart disease, or a history of stroke?

Seeing Stars After Coughing: Causes and Clinical Significance

Seeing stars (phosphenes) after coughing is most commonly caused by transient cerebral hypoperfusion resulting from markedly elevated intrathoracic pressures during forceful coughing, which reduces venous return to the heart, decreases cardiac output, and temporarily diminishes cerebral blood flow. 1

Pathophysiologic Mechanism

The phenomenon occurs through a cascade of hemodynamic changes:

• Forceful coughing generates extremely high intrathoracic pressures that impede venous return from the head and body to the right atrium, causing transient reduction in cardiac preload and stroke volume 1
• Decreased cardiac output leads to systemic hypotension and consequent cerebral hypoperfusion, manifesting as visual disturbances (phosphenes/"seeing stars"), lightheadedness, or in severe cases, loss of consciousness (cough syncope) 1
• Increased cerebrospinal fluid pressure from elevated intrathoracic pressure may also compress cerebral vessels, further reducing brain perfusion 1
• A neurally mediated reflex vasodepressor-bradycardia response to cough may compound the hypotensive effect 1

High-Risk Patient Profile

Your specific risk factors warrant careful evaluation:

• Middle-aged or older adults with large body habitus or obesity are at highest risk for generating the extreme intrathoracic pressures associated with cough-induced cerebral hypoperfusion 1
• Obstructive airways disease (asthma, COPD) predisposes to more forceful, paroxysmal coughing that generates higher intrathoracic pressures 1
• Hypertension and cardiovascular disease may impair cerebrovascular autoregulation, making the brain more vulnerable to transient hypotensive episodes 1
• History of stroke raises concern for compromised cerebrovascular reserve and increased susceptibility to hypoperfusion-related symptoms 1

Immediate Clinical Assessment Required

Screen for red flags suggesting life-threatening conditions beyond benign cough-induced hypoperfusion: 2

• Hemoptysis, unexplained weight loss, or recurrent pneumonia require immediate chest radiography and consideration of malignancy 2, 3
• Actual loss of consciousness (cough syncope) necessitates cardiac evaluation including ECG and echocardiography to exclude arrhythmias or structural heart disease 1
• New neurologic deficits, severe headache, or persistent visual changes mandate urgent neuroimaging to exclude stroke or intracranial pathology 1
• Fever, dyspnea, or signs of respiratory distress require evaluation for pneumonia or acute exacerbation of underlying lung disease 2, 4

Systematic Evaluation of Cough Etiology

Since elimination of cough eliminates the syncopal/presyncope episodes, thorough evaluation and treatment of the underlying cause of cough is mandatory: 1

Determine Cough Duration Category

• Acute cough (<3 weeks): Most commonly viral upper respiratory infection; consider post-infectious cough if following recent illness 2, 5
• Subacute cough (3-8 weeks): Typically post-infectious cough or exacerbation of underlying asthma/COPD 2
• Chronic cough (>8 weeks): Requires systematic evaluation for upper airway cough syndrome (UACS), asthma, gastroesophageal reflux disease (GERD), or non-asthmatic eosinophilic bronchitis (NAEB) 2, 3

Essential Diagnostic Workup

For patients with respiratory comorbidities experiencing cough-related visual symptoms, obtain: 2, 3

• Chest radiography to exclude pneumonia, malignancy, heart failure, or structural lung disease 2, 3
• Spirometry with bronchodilator response to assess for obstructive lung disease and asthma 2, 3
• Consider methacholine challenge testing if spirometry is normal but cough-variant asthma is suspected 2, 6

Most Common Causes in Your Population

In non-smokers not taking ACE inhibitors with normal/stable chest radiographs, three conditions account for 99.4% of chronic cough: 7

1. Upper airway cough syndrome (UACS/post-nasal drip) - 33% of cases 2
2. Asthma or cough-variant asthma - 24-32% of cases 2
3. Gastroesophageal reflux disease (GERD) - frequently coexists with other causes 2, 7

Multiple simultaneous causes occur in 59% of patients with chronic cough 7

Specific Management Based on Underlying Cause

If Asthma or Cough-Variant Asthma

Inhaled corticosteroids are first-line treatment and prevent progression to classic asthma in 30-40% of cough-variant asthma patients: 2, 6

• Start with moderate-dose inhaled corticosteroid (e.g., fluticasone 250 mcg twice daily) 2
• If incomplete response, step up ICS dose and add leukotriene inhibitor (montelukast 10 mg daily) 2
• Beta-agonists can be added in combination with ICS for additional symptom control 2

If COPD Exacerbation

Patients with COPD experiencing "recurrent cough" often have acute exacerbations rather than new episodes: 2, 5

• Optimize bronchodilator therapy (long-acting beta-agonist and/or long-acting muscarinic antagonist) 2
• Consider short course of systemic corticosteroids if significant exacerbation 2
• Smoking cessation is mandatory and may reduce or eliminate cough 2

If Upper Airway Cough Syndrome

First-generation antihistamine/decongestant combination is first-line treatment: 4

• Start with once-daily bedtime dosing, advance to twice daily if needed 4
• Add intranasal corticosteroids to decrease airway inflammation 4

If Post-Infectious Cough

Most resolve spontaneously within 3-8 weeks without specific intervention: 2, 4

• Consider ipratropium bromide inhaler for symptomatic relief 8
• First-generation antihistamine/decongestant if post-nasal drip component 4

Symptomatic Cough Suppression Strategy

If cough severity warrants suppression while treating underlying cause:

• Dextromethorphan 60 mg (not standard OTC 15-30 mg dose which is subtherapeutic) provides maximum cough reflex suppression 5, 8
• Benzonatate 100-200 mg three times daily works peripherally and has no glucose effects (relevant for diabetic patients) 8
• Avoid codeine or pholcodine - no greater efficacy than dextromethorphan but significantly more adverse effects (drowsiness, constipation, dependence) 5, 8
• Honey and lemon mixtures are as effective as pharmacological treatments for benign viral cough 5, 8

Critical Follow-Up and Monitoring

Routinely assess cough severity using validated tools and follow patients 4-6 weeks after initial visit: 2

• If cough persists beyond 3 weeks despite treatment, reassess for alternative diagnoses rather than continuing symptomatic therapy 2, 5, 8
• If cough persists beyond 8 weeks, systematic chronic cough evaluation is mandatory 2, 3
• If visual symptoms or presyncope recur despite cough treatment, consider cardiology and neurology referral to exclude cardiac arrhythmias or cerebrovascular disease 1

Common Pitfalls to Avoid

• Do not dismiss "seeing stars" as benign without evaluating the underlying cough cause - the symptom indicates significant hemodynamic compromise during coughing 1
• Do not prescribe subtherapeutic doses of dextromethorphan (15-30 mg) - maximum suppression requires 60 mg 5, 8
• Do not continue antitussive therapy beyond 2-3 weeks without reassessing the diagnosis - persistent cough requires evaluation for chronic causes 5, 8
• Do not assume "recurrent cough" in COPD patients represents new infections - most episodes are exacerbations of underlying disease requiring disease-specific management 2, 5
• Do not overlook multiple simultaneous causes - 59% of chronic cough has more than one contributing factor requiring treatment of all identified causes 7