Chronic cough in NYC — when it's not just a lingering cold

Key takeaways

• A cough is acute if it's been less than 3 weeks, subacute between 3 and 8, and chronic at 8 weeks or longer. Chronic cough has a different workup from "I've had a cold for two weeks."
• In non-smokers with a normal chest X-ray, chronic cough is almost always one of three things: upper airway cough syndrome (postnasal drip from allergy or sinusitis), asthma (often cough-variant asthma without much wheezing), or GERD (reflux without classic heartburn).
• NYC-specific contributors: subway PM2.5 (35-200 μg/m³ vs. an EPA daily limit of 35), pre-war building mold, cockroach allergen in older housing stock, and cold dry winter air from radiators.
• The single highest-value test for cough that started in the last year is usually spirometry with a bronchodilator — it diagnoses cough-variant asthma in a single 30-minute visit.
• If you've had your cough longer than 8 weeks and three rounds of antibiotics haven't helped, you almost certainly don't need a fourth round. You need a workup.

Eight weeks: the line between "just hanging on" and "something is happening"

Most colds resolve in 7-10 days. Even the bad ones (RSV in an adult, the post-COVID cough) usually fade by the 3-week mark. When a cough crosses eight weeks, the diagnostic question changes — we are no longer treating an infection that hasn't cleared. We are looking for an underlying mechanism that's been keeping the cough going all along.

The good news: in non-smokers with a normal chest X-ray (which most of our cough patients have), the cause is identifiable in 80-90% of cases, and almost always falls into one of three buckets.

The three causes that account for almost every chronic cough

Upper airway cough syndrome (postnasal drip)

This is the most common cause we see in our NYC clinic, by a wide margin. Allergic rhinitis, non-allergic rhinitis, or chronic sinusitis produces mucus that drips down the back of the throat, triggering the cough reflex.

What it feels like: A throat-clearing sensation, mucus you can feel sitting in the back of your throat, worse when you lie down at night and first thing in the morning. The cough is often productive (mucus comes up) but the volume of mucus is small.

How we treat: Identify the trigger (skin testing for environmental allergens), start an intranasal corticosteroid (Flonase, Nasacort, or prescription strength), and add an oral antihistamine or saline rinse depending on what's driving it. Most people improve within 2-4 weeks.

Asthma (often cough-variant)

About 25% of chronic cough patients in our office have asthma — and a meaningful fraction of those have cough-variant asthma, where the only symptom is the cough. No wheezing, no chest tightness, no obvious shortness of breath. Just a cough that gets worse with cold air, with exercise, or at night.

What it feels like: Worse in the morning or at night, worse with deep breaths, worse on cold or smoky days, worse with exercise. Often dry rather than productive.

How we diagnose: Spirometry with a bronchodilator. A 12% improvement in FEV1 after a puff of albuterol is the classic finding. We may also do a methacholine challenge if spirometry is borderline.

How we treat: An inhaled corticosteroid (Flovent, Symbicort, Breo) is the foundation. The cough usually responds within 2-4 weeks if asthma is the cause — and if it doesn't, we have a clear next step rather than guessing.

The patients who frustrate me are the ones who've been to three urgent cares and had three rounds of antibiotics for a cough they've had for four months. Antibiotics aren't going to help a non-bacterial cough — and most of the time, by week eight, we are not looking at a bacterial infection. We are looking at allergy, asthma, or reflux.

— Yuliya Leviyev, NP, Asthma Allergy Care & Treatment

Gastroesophageal reflux disease (GERD)

Reflux can cause cough without any classic heartburn at all. Acid reaching the larynx triggers a cough reflex, sometimes intermittently throughout the day, sometimes specifically after meals or when lying flat.

What it feels like: A dry, throat-clearing cough. Worse after eating, worse when lying down. Sometimes a hoarse voice in the morning. Patients often don't connect it to digestion.

How we treat: Lifestyle changes (no eating within 3 hours of bed, head of bed elevated 6 inches, smaller portions), a proton pump inhibitor (omeprazole, esomeprazole) for 8-12 weeks, and reevaluation. If reflux is the cause, the cough usually improves substantially by the 4-week mark.

What's specifically NYC about this

Three environmental factors hit our chronic-cough patients harder than the national average:

• Subway air. Stations measure PM2.5 in the 35-200 μg/m³ range, well above the EPA's 24-hour limit of 35. If your cough is worse on commute days vs. weekends, the daily underground exposure is plausible as a contributor — especially if you have any underlying airway hyperreactivity.
• Pre-war building mold. About 10% of NYC tenants report visible mold per the NYC Health Department's Vital Signs 2021 report. Mold-sensitive patients often present with a chronic cough that gets dramatically better when they're out of the apartment for a few days (a vacation, a hotel stay).
• Cockroach allergen. Cockroach sensitization is more than twice as high in high-asthma NYC neighborhoods (23.7%) as in lower-asthma neighborhoods (10.8%). It's a significant cough trigger and one a lot of patients don't even consider until we test for it.

When to see an allergist

Book a visit with us if any of these apply:

• Your cough has lasted more than 8 weeks
• Three or more rounds of antibiotics haven't resolved it
• The cough is interfering with sleep, work, or exercise
• You're coughing with exercise or in cold air specifically
• You suspect mold, pet dander, dust mite, or cockroach exposure
• You've already tried OTC antihistamines and nasal spray for 2-4 weeks without improvement

Go to an emergency department (or call 911) if your cough is accompanied by chest pain, coughing up blood, severe shortness of breath, or fever and confusion. Those are not chronic-cough symptoms; those are emergencies.

Frequently asked questions

Can a cough really last for months without a serious cause?

Yes. Postnasal drip, asthma, and GERD can each easily produce a cough that lasts months without progressing to anything more serious. The cause is real and treatable, but it isn't dangerous in the way patients often fear it is.

Should I get a chest X-ray for a chronic cough?

If you haven't had one in the last year and your cough has been going on more than 8 weeks, yes — it's part of the standard workup. We want to rule out infection, mass, or structural disease, even though those are uncommon causes in non-smokers.

How long does it take to diagnose chronic cough in your clinic?

Usually one or two visits. The first visit gets a full history, a focused exam, often spirometry, and frequently empirical treatment for the most likely cause. We follow up at 4-6 weeks; if you're not better, we widen the workup (allergy testing, GERD workup, possibly chest imaging or methacholine challenge).

What if I have all three at once?

Common, especially in patients with longstanding allergic rhinitis who also developed reflux. We treat the most likely contributor first, see how much of the cough resolves, then treat the next one. Sequential rather than simultaneous treatment makes it easier to know what's actually working.

Does the COVID-19 vaccine or a recent COVID-19 infection cause chronic cough?

Post-COVID cough can persist for weeks, occasionally months. If your cough started within a month of a COVID infection and is gradually improving, watchful waiting plus symptomatic treatment is usually fine. If it's not improving or is getting worse, the workup we'd do is the same as for any chronic cough.

Last reviewed

Last reviewed May 20, 2026 by Dr. Robert Tamayev, MD, PhD. Last substantive update May 20, 2026.

References

• Irwin RS et al. Chest. Classification of Cough as a Symptom in Adults and Management Algorithms. Chest. 2018;153(1):196-209.
• AAAAI / ACAAI / CHEST Joint Guideline. Diagnosis and Management of Cough: An ACCP Evidence-Based Clinical Practice Guideline. (accessed 2026-05-20)
• NYC DOHMH. NYC Vital Signs Vol. 19 No. 4 — Asthma & Housing 2021 — nyc.gov (accessed 2026-05-20).
• Vilcassim MJ et al. Black Carbon and PM2.5 Concentrations in NYC Subway Stations. Environ Sci Technol. 2014;48(24):14633-14641.
• Olmedo P et al. Neighborhood differences in exposure and sensitization to cockroach, mouse, dust mite, cat and dog allergens in NYC. PMC3271316.