What is the differential diagnosis for a persistent cough lasting 2 weeks?

From the Guidelines

For a cough lasting 2 weeks, I strongly recommend evaluating the patient for postinfectious cough, considering the duration and potential for underlying conditions such as upper airway cough syndrome, asthma, or gastroesophageal reflux disease, as suggested by the American College of Chest Physicians evidence-based clinical practice guidelines 1.

Key Considerations

• The patient's cough has lasted for 2 weeks, which may indicate a postinfectious cough, but it's essential to rule out other causes, as stated in the guidelines 1.
• The guidelines suggest considering a diagnosis of postinfectious cough when a patient complains of cough that has been present following symptoms of an acute respiratory infection for at least 3 weeks, but not more than 8 weeks 1.
• However, since the cough has only lasted for 2 weeks, it's crucial to assess for other potential causes, such as upper airway cough syndrome, asthma, or gastroesophageal reflux disease, as recommended by the guidelines 1.

Diagnostic Approach

• A thorough medical history and physical examination should be performed to identify potential underlying conditions that may be contributing to the cough, as suggested by the guidelines 1.
• If the cough is accompanied by concerning features such as fever, shortness of breath, chest pain, or blood in sputum, prompt medical attention is necessary, as indicated by the guidelines 1.

Treatment Options

• For a simple viral cough, over-the-counter remedies like dextromethorphan (15-30mg every 6-8 hours) for dry coughs or guaifenesin (200-400mg every 4 hours) for productive coughs can provide relief, as stated in the example answer.
• Honey (1-2 teaspoons) is effective for soothing throat irritation, especially before bedtime, as mentioned in the example answer.
• Inhaled ipratropium may be considered to attenuate the cough, as suggested by the guidelines 1.
• If the cough persists despite initial treatment, further evaluation and consideration of other potential causes, such as those listed in Table 1 of the uncommon causes of cough guidelines 1, may be necessary.

From the FDA Drug Label

Do not use if you are now taking a prescription monoamine oxidase inhibitor (MAOI) (certain drugs for depression, psychiatric or emotional conditions, or Parkinson’s disease), or for 2 weeks after stopping the MAOI drug. If you do not know if your prescription drug contains an MAOI, ask a doctor or pharmacist before taking this product Ask a doctor before use if you have • chronic cough that lasts as occurs with smoking, asthma or emphysema • cough that occurs with too much phlegm (mucus) Stop use and ask a doctor if • side effects occur. You may report side effects to FDA at 1-800-FDA-1088 • cough lasts more than 7 days, cough comes back, or occurs with fever, rash or headache that lasts.

For a cough that has lasted for 2 weeks, the recommendation is to stop use and ask a doctor because it could be a sign of a serious condition 2.

• The product should not be used for a chronic cough or a cough with too much phlegm without consulting a doctor.
• If the cough lasts more than 7 days, or if it comes back, or if it occurs with fever, rash, or headache, a doctor should be consulted.

From the Research

Cough Duration and Treatment

• A cough lasting for 2 weeks can be a symptom of various conditions, including acute sinusitis, bronchiectasis, or allergic rhinitis 3, 4, 5.
• Studies have shown that antibiotics such as amoxicillin-clavulanate and azithromycin can be effective in treating acute sinusitis and bronchiectasis, with symptom resolution rates ranging from 29.7% to 65% by day 14 3, 4.
• The use of intranasal corticosteroids, such as fluticasone, can also be beneficial in treating allergic rhinitis and reducing nasal symptoms 5, 6.
• For chronic cough, defined as a daily cough lasting longer than 8 weeks, treatment guidelines recommend stepwise treatment with specific nonpharmacologic therapies and pharmacologic agents, with new targeted therapies currently under development 7.

Treatment Options

• Amoxicillin-clavulanate and azithromycin are commonly used antibiotics for treating acute sinusitis and bronchiectasis 3, 4.
• Intranasal corticosteroids, such as fluticasone, can be used to treat allergic rhinitis and reduce nasal symptoms 5, 6.
• Combination therapy with azelastine hydrochloride nasal spray and fluticasone propionate nasal spray may provide a substantial therapeutic benefit for patients with seasonal allergic rhinitis 6.
• New targeted therapies, such as purinergic 2X3 receptor antagonists and neurokinin-1 receptor antagonists, are currently under development for the treatment of chronic cough 7.