If you’ve been coughing for more than eight weeks, you’re not alone. About 1 in 10 adults deal with a chronic cough that won’t go away. And chances are, it’s not from a cold or the flu. Most of the time, it’s caused by one of three things: GERD, asthma, or postnasal drip - now more accurately called upper airway cough syndrome. The good news? You don’t need dozens of tests or months of guesswork. A smart, step-by-step approach can get you answers - and relief - in weeks.
Start by Ruling Out the Red Flags
Before you even think about reflux or allergies, you need to make sure nothing serious is going on. A chronic cough can sometimes be a sign of lung cancer, tuberculosis, or heart failure. That’s why your doctor will first look for warning signs: coughing up blood, unexplained weight loss, fever that won’t quit, or swelling in your legs. If any of these are present, you’ll need imaging or specialist referral right away. Another big one: medications. If you’re taking an ACE inhibitor - drugs like lisinopril or enalapril - for high blood pressure, that’s a likely culprit. Up to 35% of people on these drugs develop a dry, tickly cough within weeks or months. Stopping the drug often clears it up in days. Don’t quit on your own, but do bring it up with your doctor.The Big Three: GERD, Asthma, and Upper Airway Cough Syndrome
Once the red flags are ruled out, the focus shifts to the big three. Together, they cause 80-95% of chronic cough cases in people who don’t smoke and aren’t on ACE inhibitors. The trick? They don’t always show up the way you’d expect.GERD: Silent Reflux Is Common
You might think GERD means heartburn. But for many people with GERD-related cough, there’s no burning at all. This is called silent reflux. Instead, you might notice your cough gets worse after eating, lying down, or at night. You may feel a lump in your throat or have a bitter taste in your mouth in the morning. The old approach was to just start you on a high-dose proton pump inhibitor (PPI) like omeprazole for 4-8 weeks. But here’s the catch: only 50-75% of people with GERD-related cough respond. And up to 40% of people who take PPIs for no reason still feel better - thanks to the placebo effect. Newer guidelines from the American College of Gastroenterology (March 2024) now say: don’t start PPIs unless there’s strong evidence of reflux. That means if you’re going to try this, you need to track your symptoms. Did the cough improve after 4 weeks? If not, it’s probably not GERD.Asthma: Cough-Only Asthma Is Real
Asthma doesn’t always mean wheezing. In fact, about 25% of adults with chronic cough have what’s called cough variant asthma. Your lungs sound normal. You don’t feel short of breath. But you cough - especially at night, after exercise, or when you breathe cold air. The standard test is spirometry. If your lung function looks normal, the next step is a methacholine challenge. This test irritates your airways just enough to see if they overreact. A positive result (a 12% drop in FEV1 after inhaling methacholine) confirms asthma. But even if that test is negative, your doctor might still try a 4-week trial of an inhaled corticosteroid. If your cough improves, it’s likely asthma. One thing to know: cough variant asthma often responds faster than classic asthma. You might see results in just 1-2 weeks.Postnasal Drip (Upper Airway Cough Syndrome)
This is the most common cause of chronic cough - affecting up to 62% of cases. But the term “postnasal drip” is outdated. The real issue isn’t mucus dripping down your throat. It’s that your throat and airway become hypersensitive. Even tiny amounts of mucus or irritants trigger the cough reflex. Symptoms? A constant need to clear your throat, nasal congestion, or a feeling of something stuck in the back of your throat. You might also have seasonal allergies or a history of sinus infections. The best way to test for this? A 2-3 week trial of a first-generation antihistamine (like brompheniramine) plus a decongestant (like pseudoephedrine). Second-gen antihistamines (like loratadine) don’t work as well for cough. Why? Because they don’t block the histamine receptors in the throat that trigger coughing. If your cough improves within 1-2 weeks, it’s likely UACS. If not, move on.How the Workup Actually Works
There’s no single test that confirms any of these three. That’s why the process is sequential. Here’s what it looks like in practice:- Get a chest X-ray. If it’s normal, you can rule out pneumonia, tumors, or bronchiectasis.
- Do spirometry. If it’s abnormal, asthma is likely. If normal, proceed.
- Try UACS treatment first - antihistamine + decongestant for 2-3 weeks.
- If no improvement, try asthma treatment - inhaled steroid for 4 weeks.
- If still no improvement, try GERD treatment - PPI for 4-8 weeks.
What If Nothing Works?
About 10-30% of people don’t improve after trying all three. That’s when you dig deeper. Possible causes include:- Chronic aspiration - swallowing food or liquid into the lungs
- Pertussis (whooping cough) - rare in adults, but possible if you haven’t had a booster
- Eosinophilic bronchitis - inflammation without asthma
- Chronic refractory cough (CRC) - where the cough reflex is just too sensitive
What You Can Do Now
You don’t have to wait for a doctor to start helping yourself:- If you smoke - quit. Smoking worsens all three causes.
- Track your cough. When does it happen? After meals? At night? Around pets? Write it down.
- Avoid triggers: spicy food, alcohol, caffeine, lying down after eating.
- Elevate your head while sleeping - even 6 inches helps with reflux.
- Use a humidifier if your air is dry - especially in winter.
Common Mistakes to Avoid
- Antibiotics: Only 1-5% of chronic coughs are from bacterial infections. Don’t take them unless you have a confirmed infection. - Over-testing: A chest CT scan won’t help if your X-ray is normal. It exposes you to radiation equivalent to 74 chest X-rays for a 0.1% chance of finding cancer. - Skipping the trial: If your doctor says “try this for 3 weeks,” do it. Half of people give up too soon. - Using the wrong meds: Second-gen antihistamines like cetirizine won’t help UACS. You need the older ones that cross into the throat tissue.Bottom Line
Chronic cough isn’t a mystery. It’s usually one of three treatable conditions. The key is not to rush into expensive or invasive tests. Start simple. Follow a clear sequence. Give each treatment a fair shot. And if you’re still coughing after all three, you’re not alone - but you’re not out of options either.How long does a chronic cough usually last before it’s diagnosed?
By definition, a chronic cough lasts more than 8 weeks. But many people wait 6-12 months before seeking help, often trying OTC cough syrups or antibiotics first. The sooner you start the proper workup - chest X-ray, spirometry, and targeted treatment trials - the faster you’ll find relief. Most people see improvement within 2-4 weeks if the correct cause is identified.
Can GERD cause cough without heartburn?
Yes. In fact, up to 70% of people with GERD-related cough have no classic heartburn. This is called silent reflux. The acid irritates the nerves in the throat and voice box, triggering coughing - even if it never reaches the esophagus. Nighttime cough, throat clearing, or a sour taste in the morning are more common signs than burning.
Is postnasal drip the same as allergies?
Not exactly. Allergies can cause postnasal drip, but not all postnasal drip is from allergies. Sinus infections, colds, dry air, or even spicy food can trigger it. The key difference is in treatment: antihistamines help if allergies are the trigger, but decongestants are needed to reduce mucus production. That’s why first-gen antihistamines plus decongestants are the standard trial - they target both the mucus and the hypersensitive nerves.
Do I need a CT scan for chronic cough?
No - not if your chest X-ray is normal. A CT scan exposes you to high levels of radiation and rarely finds anything new in people with no red flags. The American Thoracic Society and European Lung Foundation both recommend against routine CT scans. Only consider it if you have unexplained weight loss, coughing blood, or abnormal findings on X-ray or exam.
What’s the best way to track my cough at home?
Keep a simple diary: note the time of day, what you were doing, and how bad the cough felt (on a scale of 1-10). Also record triggers: eating, lying down, cold air, talking, or exposure to smoke. Apps like the Hull Cough Questionnaire (available online) can help score your symptoms. If your cough improves by 50% or more during a treatment trial, that’s a strong sign you’ve found the cause.
Why do some people keep coughing even after treatment?
Sometimes, the cough reflex becomes oversensitive - even after the original trigger (like GERD or allergies) is gone. This is called chronic refractory cough. It’s not uncommon, affecting up to 20% of people who’ve had chronic cough for years. New medications like gefapixant target this nerve sensitivity directly. If you’ve tried everything and still cough, ask your doctor about cough hypersensitivity testing or referral to a specialist clinic.
i’ve had this cough for 11 months and i just thought it was allergies or stress lol
turns out i was on lisinopril and never connected the dots. stopped it and cough was gone in 5 days. why do docs never ask about meds first??