What is the cause of persistent coughing fits three weeks after being treated with azithromycin (Zpack) and benzocaine (Tessalon Perles) for atypical pneumonia (walking pneumonia)?

From the Guidelines

You should contact your healthcare provider for a follow-up evaluation to determine the cause of your persistent coughing fits three weeks after being treated for walking pneumonia with azithromycin (Z-pack) and tessalon perles. 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, consider a diagnosis of postinfectious cough, as stated in the American College of Chest Physicians (ACCP) evidence-based clinical practice guidelines 1. The guidelines suggest that in patients with subacute postinfectious cough, multiple pathogenetic factors may contribute to the cause of cough, including postviral airway inflammation, upper airway cough syndrome (UACS), asthma, and gastroesophageal reflux disease 1. Some key points to consider in the management of postinfectious cough include:

• Therapy with antibiotics has no role, as the cause is not bacterial infection 1
• Consider a trial of inhaled ipratropium as it may attenuate the cough 1
• In patients with postinfectious cough, when the cough adversely affects the patient’s quality of life and when cough persists despite use of inhaled ipratropium, consider the use of inhaled corticosteroids 1
• For severe paroxysms of postinfectious cough, consider prescribing 30 to 40 mg of prednisone per day for a short, finite period of time when other common causes of cough have been ruled out 1 It is essential to note that the optimal treatment for postinfectious cough is not known, and a thorough evaluation by a healthcare provider is necessary to determine the best course of action. In the meantime, staying well-hydrated, using a humidifier to moisten the air, avoiding irritants like smoke or strong scents, and trying honey in warm tea to soothe the throat (if not allergic or diabetic) may help alleviate symptoms. If new symptoms like fever, chest pain, or shortness of breath develop, seek medical attention promptly as this could indicate a complication or new infection.

From the FDA Drug Label

WARNINGS SECTION Hypersensitivity Serious allergic reactions, including angioedema, anaphylaxis, and dermatologic reactions including Stevens Johnson Syndrome and toxic epidermal necrolysis have been reported rarely in patients on azithromycin therapy. Although rare, fatalities have been reported. Despite initially successful symptomatic treatment of the allergic symptoms, when symptomatic therapy was discontinued, the allergic symptoms recurred soon thereafter in some patients without further azithromycin exposure. Clostridium Difficile-associated diarrhea Clostridium difficile associated diarrhea (CDAD) has been reported with use of nearly all antibacterial agents, including azithromycin, and may range in severity from mild diarrhea to fatal colitis CDAD must be considered in all patients who present with diarrhea following antibiotic use. Careful medical history is necessary since CDAD has been reported to occur over two months after the administration of antibacterial agents.

The cause of persistent coughing fits three weeks after being treated with azithromycin for atypical pneumonia may be related to allergic reactions or Clostridium Difficile-associated diarrhea (CDAD), as these conditions have been reported in patients taking azithromycin 2. However, the FDA label does not directly link these conditions to coughing fits.

• Allergic reactions can recur after discontinuation of symptomatic therapy.
• CDAD can occur over two months after antibiotic use and may present with various symptoms. It is essential to consider these potential causes and consult a healthcare professional for proper evaluation and management.

From the Research

Possible Causes of Persistent Coughing

• The exact cause of persistent coughing fits three weeks after being treated with azithromycin and benzocaine for atypical pneumonia is not directly addressed in the provided studies 3, 4, 5, 6, 7.
• However, the studies suggest that chronic cough can be caused by various factors, including upper airway cough syndrome, asthma, gastroesophageal reflux disease, and cough reflex hypersensitivity 4, 5, 6, 7.
• It is possible that the patient's cough is not fully resolved due to an underlying condition that was not adequately treated or addressed during the initial treatment with azithromycin and benzocaine 3, 4, 5.

Treatment-Resistant Cough

• A study on the effects of azithromycin in treatment-resistant cough found that low-dose azithromycin for 8 weeks did not significantly improve cough symptoms compared to placebo 3.
• However, the study suggested that macrolides like azithromycin may have a place in the treatment of chronic cough associated with asthma, which is worthy of further investigation 3.

Evaluation and Management of Chronic Cough

• The evaluation of patients with chronic cough should include a focused history and physical examination, chest radiography, and further testing as needed 5.
• Empiric treatment for gastroesophageal reflux disease and avoidance of cough-evoking irritants like cigarette smoke may be beneficial in managing chronic cough 5.
• Recognizing cough reflex hypersensitivity as a treatable trait offers new avenues for management, particularly for patients with persistent cough despite etiology-targeted therapies 6.