When the Cough Becomes the Problem

This article explains what causes a cough to become chronic, when to seek help, and what treatment options can finally bring relief.

There's a particular kind of exhaustion that comes with chronic cough. Not just physical - though the intercostal muscles between the ribs get sore, and the abs feel like they've done a thousand crunches they didn't sign up for. It's the social exhaustion. The coughing in the cinema, in the library, during the quiet part of the wedding vows. The constant calculation of where you can and can't be.

I've noticed people with chronic cough develop this... wariness. They scan rooms for exit routes. They position themselves near doorways. One man told me he stopped going to church because he couldn't bear the looks anymore. "It's not that people are mean," he said. "It's that they're worried. And their worry makes me feel diseased."

What interests me about chronic cough - beyond the diagnostic algorithm, beyond the treatment protocols - is how profoundly it affects quality of life in ways that don't show up on any test. Sleep fragmentation, social isolation, urinary incontinence from repeated forceful coughing, even rib fractures in severe cases. The Global Burden of Disease studies consistently rank chronic cough as one of the most disabling respiratory conditions, not because it's life-threatening, but because it's life-invading.

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The Physiology of Why Cough Won't Stop

To understand why some coughs persist for months, we need to understand the cough reflex arc - the neurological circuit that turns irritation into that explosive expulsion of air we call a cough.

The process starts with cough receptors in the airways. These are specialised nerve endings that respond to mechanical irritation (like mucus), chemical irritation (like stomach acid or cigarette smoke), or inflammatory mediators (like histamine or bradykinin - chemicals released during inflammation that trigger various responses including cough). When stimulated, these receptors send signals via the vagus nerve - the main nerve connecting the brain to many organs including the lungs and digestive system - to the cough centre in the brainstem.

The brainstem coordinates the response: deep inspiration, closure of the glottis (the opening between the vocal cords), contraction of the expiratory muscles, then sudden glottic opening and the violent expulsion of air at velocities that can exceed 500 miles per hour. It's actually quite an impressive bit of physiological engineering when it's protecting you from aspirating your tea.

The problem in chronic cough is that this reflex becomes hypersensitive. The threshold for triggering a cough drops. Things that wouldn't normally provoke coughing - talking, laughing, perfume, cold air - suddenly do. The medical term is "cough hypersensitivity syndrome," and it's probably the final common pathway for most chronic cough, regardless of the initial trigger.

What's fascinating is that this hypersensitivity can persist even after you've treated the original cause. The airway develops a kind of... memory. The nerves stay primed. Which is why chronic cough treatment often requires addressing both the underlying cause and the sensitised reflex itself.

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GERD: The Silent Reflux Problem

Gastroesophageal reflux disease - GERD - is one of the most common causes of chronic cough, but it's also one of the most misunderstood. People expect heartburn. They expect to feel the burn rising up their chest. But in a significant proportion of cases, especially when cough is the predominant symptom, there's no heartburn at all.

This is called "silent reflux" or laryngopharyngeal reflux, and it's a different beast from typical GERD. In typical GERD, stomach acid sits in the lower oesophagus long enough to cause that burning sensation. In laryngopharyngeal reflux, small amounts of acid or pepsin - an enzyme from the stomach that breaks down proteins - reach the throat and larynx, irritating the sensitive tissues there and triggering cough receptors.

The larynx is exquisitely sensitive to acid. It doesn't take much. Even brief exposure, just a few times a day, can be enough to set off chronic coughing.

The clues are subtle. Hoarseness, especially in the morning. The need to clear the throat constantly. A sensation of something in the throat that won't shift. Cough that worsens after meals or when lying down. Sometimes people notice a sour or bitter taste, but often there's nothing obvious at all.

Diagnosing GERD-related cough is tricky because there's no perfect test. We can do a trial of proton pump inhibitors (PPIs like omeprazole or pantoprazole - medications that dramatically reduce stomach acid production), but the response isn't immediate. It takes 8-12 weeks of twice-daily PPI therapy before we see improvement, because we're not just suppressing acid - we're waiting for the irritated laryngeal tissue to heal and the hypersensitive cough reflex to calm down.

Some guidelines suggest 24-hour pH monitoring or oesophageal manometry - a test that measures the pressure and coordination of muscle contractions in the oesophagus - but honestly, most of the time we start with an empirical trial of treatment. If someone has chronic cough, no smoking history, normal chest X-ray, and subtle reflux symptoms, we try PPIs and see what happens.

The non-pharmacological stuff matters just as much. Weight loss if overweight. Elevating the head of the bed by 15-20 centimetres. Avoiding late meals. Cutting back on coffee, alcohol, chocolate, peppermint - all the things that relax the lower oesophageal sphincter and make reflux worse.

What surprises people is how long it takes. They expect improvement in days. But the airway inflammation from chronic acid exposure doesn't resolve overnight. Healing tissue, resetting hypersensitive nerves - that's a weeks-to-months process.

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ACE Inhibitors: The Medication Nobody Connects

ACE inhibitors - medications like lisinopril, enalapril, perindopril - are among the most commonly prescribed drugs for high blood pressure and heart failure. They're effective, well-tolerated, cheap. But they cause chronic cough in about 10-20% of people who take them.

The mechanism is interesting. ACE inhibitors block the enzyme that breaks down bradykinin, a peptide that accumulates and irritates cough receptors in the airways. The cough is usually dry, persistent, and can start anywhere from a few days to several months after starting the medication.

What makes this frustrating is that people don't always make the connection. They've been on lisinopril for six months. The cough started two weeks ago. It doesn't occur to them - or sometimes to their doctor - that a medication they've been taking for half a year could suddenly cause a new symptom.

But that's how it works. The bradykinin accumulation is gradual. The cough threshold slowly lowers. Then one day it tips over, and suddenly you're coughing constantly.

The diagnostic trick is simple: ask about all medications, including ones started months ago. If someone is on an ACE inhibitor and has unexplained chronic cough, stop it. Switch to an angiotensin receptor blocker (ARB) like candesartan or irbesartan, which has a similar blood pressure effect but doesn't affect bradykinin. The cough usually resolves within 1-4 weeks.

The delay in resolution can be unsettling. People stop the medication and expect immediate relief. But the accumulated bradykinin takes time to clear, and the hypersensitive cough reflex takes time to settle. I usually tell people to give it a month. If the cough isn't improving by then, we're looking elsewhere.

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Upper Airway Cough Syndrome: It's Not Just Postnasal Drip

Upper airway cough syndrome - UACS - used to be called postnasal drip syndrome, but the name was changed because it's not always about drip. Sometimes it's just inflammation and mucus in the sinuses and nasopharynx triggering a cough reflex, even without visible drainage.

The classic presentation is someone who feels mucus in the back of their throat, constantly clearing, especially in the morning. Frequently they have a history of allergic rhinitis - hay fever - or chronic sinusitis. Sometimes there's a nasal quality to their voice, or they mention nasal congestion, though not always.

The diagnosis is largely clinical. We look for signs of postnasal drainage on examination - mucus visible in the posterior pharynx, a cobblestone appearance from lymphoid hyperplasia. We ask about triggers: seasons, dust, pets, mould. Sometimes we see it on a CT sinus scan, though that's not always necessary.

Treatment is first-generation antihistamines like chlorpheniramine or promethazine, which are more effective than the newer non-sedating antihistamines for suppressing cough. We add nasal corticosteroids (fluticasone, mometasone) to reduce inflammation. Sometimes a short course of oral prednisolone to break the cycle.

What I find interesting is how often UACS coexists with other causes. Someone might have mild asthma and postnasal drip. Or GERD and UACS. The cough becomes multifactorial, and treating one cause doesn't fully resolve it because the other is still contributing.

This is where chronic cough gets complex. It's rarely just one thing. The airways have been irritated for so long that multiple pathways are now involved. The cough has become... layered.

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When It's Not the Big Four: The Uncommon Causes

Most chronic cough is asthma, GERD, ACE inhibitors, or UACS. But about 10% of the time, it's something else. These are the cases that require more investigation.

Bronchiectasis - permanent dilation of the airways from repeated infections or inflammation - causes chronic productive cough with purulent sputum. It shows up on high-resolution CT chest scans as dilated, thickened airways. The treatment involves physiotherapy to clear secretions, sometimes long-term antibiotics, occasionally inhaled antibiotics for pseudomonas colonisation.

Chronic bronchitis - defined as productive cough for at least three months per year for two consecutive years - is usually related to smoking, though not always. The airways are chronically inflamed, producing excess mucus. Smoking cessation is the primary treatment. Bronchodilators and inhaled corticosteroids sometimes help.

Interstitial lung disease - a group of disorders causing scarring of lung tissue - can present with chronic dry cough, often associated with progressive shortness of breath. The cough is thought to arise from stimulation of irritant receptors in the fibrotic lung tissue. High-resolution CT shows characteristic patterns depending on the specific disease. Treatment depends on the underlying cause.

Lung cancer is the rare but serious cause we always consider, especially in smokers or those with concerning symptoms - haemoptysis (coughing up blood), weight loss, night sweats. A chest X-ray is usually the first step, followed by CT if there's anything suspicious.

Pertussis - whooping cough - occasionally causes chronic cough in adults who were vaccinated as children but whose immunity has waned. The classic "whoop" isn't always present. Sometimes it's just a persistent, paroxysmal cough that lasts for months. We test with PCR or serology if the history fits.

Psychogenic cough is a diagnosis of exclusion, but it's real. Usually in adolescents, sometimes in adults. A loud, barking cough that disappears during sleep. No organic cause found despite extensive investigation. Treatment is behavioral therapy, sometimes speech therapy. It's not that the person is faking - it's that the cough has become a learned reflex, a habit loop that needs to be consciously broken.

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The Problem With Chronic Cough: It Becomes Self-Sustaining

Here's what makes chronic cough particularly difficult: after a certain point, the cough itself becomes the problem. Even if you treat the original cause, the airways remain hypersensitive. The cough reflex has been reset to a lower threshold. Small irritants that wouldn't bother a normal person now trigger violent coughing fits.

This is cough hypersensitivity syndrome, and it's increasingly recognized as the final common pathway in chronic cough. The neurological circuits have been rewired. The vagal nerve endings in the airways fire more easily. The brainstem cough centre responds more readily.

We're learning that some of this is mediated by TRPV1 receptors - transient receptor potential vanilloid 1 receptors, the same ones activated by capsaicin in chili peppers - which become upregulated in chronic cough. These receptors make the airways hypersensitive to temperature changes, chemical irritants, and mechanical stimulation.

Treatment of cough hypersensitivity syndrome is challenging. We address the underlying causes first - asthma, GERD, UACS. But if the cough persists despite optimal treatment, we sometimes try neuromodulators: low-dose amitriptyline, gabapentin, pregabalin. These medications dampen the neural hypersensitivity, raising the cough threshold back to something more reasonable.

Speech pathology and cough suppression therapy can also help. Techniques to consciously suppress the urge to cough, distraction strategies, swallowing techniques - essentially retraining the reflex arc.

The response is variable. Some people improve significantly. Others find only modest benefit. But the key insight is recognizing that after months of coughing, the nervous system itself has changed. We're not just treating an irritated airway anymore. We're treating altered neural processing.

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What Makes Chronic Cough So Exhausting

I think what gets lost in all the diagnostic algorithms and treatment protocols is the sheer toll chronic cough takes. The sleep disruption alone is profound. People cough themselves awake multiple times per night. They wake up exhausted, muscles aching from repeated forceful contractions.

The social isolation is real. People avoid gatherings, theatres, restaurants - anywhere quiet where their cough will draw attention. They develop anxiety about coughing, which paradoxically makes the cough worse because anxiety lowers the cough threshold.

Urinary incontinence from stress on the pelvic floor during coughing fits is common but rarely discussed. Rib fractures from severe persistent coughing are rare but do happen, especially in older people or those with osteoporosis.

Quality of life studies show that chronic cough impacts daily functioning as much as severe COPD or heart failure. But because it doesn't kill you, because it looks benign on imaging, it's often dismissed or undertreated.

I find myself thinking about that. The conditions that don't threaten life but steal quality of life. The symptoms that are "just" annoying until they're not - until they've eroded your capacity to function normally, to enjoy simple pleasures, to feel at ease in your own body.

Chronic cough is one of those. And recognizing it - really seeing how much it affects someone - is half the battle.