What medication is appropriate for a 13-year-old girl with a dry (non‑productive) cough lasting more than one week and no red‑flag symptoms?

Management of Non-Productive Cough in a 13-Year-Old Female

For a 13-year-old girl with a dry, non-productive cough lasting more than one week without red-flag symptoms, the recommended approach is watchful waiting with reassessment in 2-4 weeks, as this most likely represents post-viral cough or acute bronchitis that will resolve spontaneously. 1

Initial Assessment and Classification

This patient has a non-specific dry cough (cough without other respiratory symptoms or concerning features) that has persisted beyond one week but has not yet reached the 4-week threshold for "chronic cough." 1

Key Red Flags to Rule Out (Must Be Absent)

• Coughing with feeding (suggests aspiration) 1
• Digital clubbing (indicates chronic lung disease) 1
• Respiratory distress, hypoxia, or cyanosis 2
• High fever ≥39°C/102.2°F 2
• Paroxysmal cough with post-tussive vomiting or inspiratory "whoop" (pertussis) 2
• Hemoptysis or failure to thrive 1

Environmental and Social Factors to Address

• Evaluate and eliminate tobacco smoke exposure, which is a critical modifiable risk factor for persistent cough 2
• Assess for other environmental pollutants or irritants 1
• Explore parental and patient concerns and expectations about the cough 1

Management Strategy for Week 1-4

No medication is indicated at this stage. The evidence strongly supports a "watch, wait, and review" approach for non-specific dry cough in children. 1

What NOT to Do

• Do not prescribe antibiotics for dry cough, as antibiotics are only indicated for chronic wet/productive cough 1
• Do not prescribe asthma medications (inhaled corticosteroids or bronchodilators) unless there is clear evidence of asthma with wheeze, dyspnea, or documented reversible airway obstruction 1
• Do not use over-the-counter cough suppressants (such as dextromethorphan), as they lack proven efficacy in children and adolescents 3, 4
• Do not empirically treat for GERD, upper airway cough syndrome, or asthma without specific clinical features supporting these diagnoses 1

Supportive Care Recommendations

• Honey may be used for symptomatic relief in adolescents, as it provides effective cough relief without adverse effects 3
• Encourage adequate hydration to thin respiratory secretions 3
• Advise against lying flat, as upright positioning improves cough effectiveness 3

Follow-Up Timeline and Escalation

At 2-4 Weeks

• Reassess the patient to determine if the cough has resolved or persists 1
• Most post-viral coughs resolve within 1-3 weeks, though 10% may persist beyond 20-25 days 3, 5

If Cough Persists to 4 Weeks (Chronic Cough Threshold)

At 4 weeks, the cough becomes "chronic" and requires systematic evaluation: 1, 3

• Obtain chest radiograph to exclude structural abnormalities, pneumonia, or foreign body 1, 3
• Perform spirometry (pre- and post-bronchodilator) if the patient can reliably perform the test 1, 3
• Re-classify the cough as wet/productive versus dry to guide further management 1, 3

If Cough Remains Dry at 4 Weeks

• Consider asthma only if there are additional features such as wheeze, nocturnal symptoms, exercise intolerance, or documented reversible airway obstruction 1, 3
• Consider less common causes: tracheomalacia, habit cough, or functional disorders 1
• A trial of inhaled corticosteroids may be considered if asthma features are present, but should be ceased after 2-4 weeks if there is no response 1

If Cough Becomes Wet/Productive

• Prescribe 2 weeks of antibiotics targeting common respiratory bacteria (Streptococcus pneumoniae, Haemophilus influenzae, Moraxella catarrhalis), such as amoxicillin or amoxicillin-clavulanate 1
• If wet cough persists after 2 weeks of antibiotics, prescribe an additional 2 weeks 1
• If wet cough persists after 4 weeks total of antibiotics, perform further investigations including flexible bronchoscopy with quantitative cultures 1

Critical Clinical Pitfalls to Avoid

The most common error is over-diagnosing asthma based on cough alone. 1, 6 Studies demonstrate that isolated chronic cough in children is rarely asthma, and most children with persistent cough without wheeze do not have airway inflammation consistent with asthma. 1 The term "cough variant asthma" should not be used in children, as it leads to inappropriate long-term asthma treatment. 4, 6

Do not assume a "positive" response to medication trials is due to the medication itself, given the favorable natural history of cough resolution over time. 4 Any therapeutic trial should be time-limited (2-4 weeks maximum) and medications should only be continued if there is clear benefit and relapse upon discontinuation. 1, 5