Dry vs. productive cough: cough suppressants vs. expectorants, what works

Pe scurt: Tell a dry cough from a productive one. Butamirate, dextromethorphan, ambroxol, NAC, codeine — when to choose what. Cochrane evidence and EMA recommendations.

"Miss, what can you give me for a cough?" is the worst-worded reason to buy something in a pharmacy. Because a dry cough and a productive cough call for completely different molecules, and the wrong combination (a cough suppressant for a productive cough) can worsen a bronchitis picture. Let us tell them apart clearly.

Two coughs, two approaches

  • Dry cough — no sputum, irritative, triggered by upper respiratory viral infections, smoke, ACE inhibitors (captopril, enalapril, perindopril), gastro-oesophageal reflux, asthma. Here the point of cough suppressants is real.
  • Productive (wet) cough — with sputum. A clearance mechanism — you are trying to expel secretions. Here cough suppressants are counterproductive; you need mucolytics / expectorants.

Cough suppressants — how they act and which exist

Active substanceMechanismStatusRO examples
CodeineCentral opioid, suppresses the cough centreP-RF (controlled substance)Rinofug Plus, Tussin
DextromethorphanCentral NMDA antagonist, non-opioidOTCCalmotusin, Tussin DM
ButamirateNon-opioid, centralOTCSinecod, Stoptussin (combined)
LevodropropizinePeripheral, on bronchial sensory receptorsOTCLevopront
CloperastineCentral suppressant + mildly antihistaminicOTCPlurituss
PholcodineWeak opioidWithdrawn in RO/EU 2022 — risk of cross-anaphylaxis with neuromuscular blockers

Mucolytics and expectorants

Active substanceMechanismRO examples
Acetylcysteine (NAC)Breaks the disulfide bonds of mucin → thins itACC, Fluimucil, Mucosolvin, Solmucol
CarbocisteineModifies the mucin structureBronchosolvin, Carbosin
AmbroxolStimulates surfactant, thinsMucosolvan, Halixol, Brontex, Ambroxol LPH
BromhexineAmbroxol precursorBisolvon, Bromhexin Atb
ErdosteineMucomodulator, antioxidantErdomed
GuaifenesinOsmotic expectorantcomponent in Robitussin Expectorant

What the evidence shows

Cochrane ("Over-the-counter (OTC) medications for acute cough in children and adults in community settings", 2014, 2024 update) conclusion: limited evidence that cough suppressants or mucolytics bring clear benefits in acute viral cough. The placebo effect is large in cough — any sweet syrup partly soothes.

Exceptions with a clearer benefit:

  • NAC and carbocisteine in COPD with frequent exacerbations — they reduce the exacerbation rate (the Poole et al. meta-analysis).
  • Dextromethorphan in persistent dry cough — a modest reduction in frequency.
  • Codeine and opioids — effective, but an unfavourable risk-benefit profile in uncomplicated acute cough.

Practical rules

  1. Dry, irritative cough, no fever for >3 days: butamirate (Sinecod) or levodropropizine. Good hydration, humidified air.
  2. Productive cough with thick sputum: ambroxol or NAC, plenty of fluids (1.5-2 L/day). Do NOT add a cough suppressant — you block the expectoration.
  3. Cough + blocked nose: saline nasal spray (Sinomarin, Marimer) ± xylometazoline for 3-5 days. The cough often comes from post-nasal drip.
  4. Cough + wheezing: it is not just viral — investigate asthma; inhaled salbutamol as needed.
  5. Dry, persistent cough >8 weeks: medical evaluation — asthma, GORD, ACE inhibitor, chronic sinusitis, fibrosis, neoplasm.

Specific warnings

  • Codeine — contraindicated under 12 years (EMA 2015), caution in rapid CYP2D6 metabolisers.
  • NAC — caution in asthma patients (rare bronchospasm), not combined with antibiotics in the same hour (chelation).
  • Ambroxol and bromhexine — EMA alert 2015, severe skin reactions (SJS/TEN), rare but serious.
  • In children <2 years — OTC cough suppressants and mucolytics are contraindicated or strictly indicated (they thin too much, risk of choking on sputum).
  • Pholcodine — withdrawn from the EU in 2022 after a signal of cross-anaphylaxis with neuromuscular blockers in general anaesthesia.

Non-drug remedies with evidence

  • Honey — 1-2 teaspoons in a child >1 year, before bedtime. Cochrane: a modest but consistent effect in acute cough in children.
  • Hydration — water, teas, warm soup.
  • Steam inhalation (with or without essential oils, with caution in children).
  • Saline nasal spray — reduces post-nasal drip cough.
  • Lozenges with menthol/eucalyptus — a mild symptomatic effect.

RO reimbursement and prices

Most cough suppressants and mucolytics are OTC. Codeine is P-RF (a controlled substance under Law 339/2005). Ambroxol, NAC, butamirate have 50% reimbursement on List B/C2 only in chronic pulmonary indications. The price of ACC 600 mg granules syrup or ambroxol solution varies between chains — Catena, Dona, Help Net, Farmacia Tei, Dr.Max — compared on HartaFarmacii.

Frequently asked questions

Why do I have a dry cough after getting over a cold?
Post-viral hyper-reactivity — it lasts 3-6 weeks. Soothe with butamirate or a short inhaled corticosteroid (on advice).
Does NAC really reduce mucus?
Yes, it thins it in vitro and clinically in thick sputum. A real benefit in COPD, more modest in a simple cold.
Can I give Sinecod to a child?
From 2 years, drops; syrup from 3 years — strictly by weight. Not under 2 years.
What does a "cough with blood" mean?
Minimal haemoptysis (streaks) after a coughing effort can be innocent; massive or persistent haemoptysis — an emergency, immediate radiological evaluation.
Does honey work in adults?
Less studied than in children, but plausible — a demulcent effect.
Why did the pharmacist tell me "do not take Sinecod with ambroxol"?
Because the suppressant stops the cough that should expel the thinned sputum — a contradictory effect, with a possible bronchial plug.

Chronic cough >8 weeks: when to worry

The standard definition: a cough lasting >8 weeks in an adult, >4 weeks in a child. The most frequent causes, in order of probability in a non-smoker:

  1. Post-nasal drip syndrome (chronic, allergic rhinosinusitis) — 30-40%. Test: responds to an intranasal corticosteroid + a second-generation antihistamine.
  2. Cough-variant asthma — 20-30%. Spirometry with a bronchomotor test or FeNO. Responds to an inhaled corticosteroid.
  3. GORD — 20-30%. Responds to a double-dose PPI for 8-12 weeks; possibly oesophageal pH-metry.
  4. ACE-inhibitor-induced cough (enalapril, perindopril, ramipril) — 5-20% of users. Solution: switch to a sartan (losartan, valsartan).
  5. Non-asthmatic eosinophilic bronchitis — responds to an inhaled corticosteroid.
  6. Rare causes: tuberculosis, bronchopulmonary neoplasm, pulmonary fibrosis, chronic pulmonary embolism, congestive heart failure, a foreign body, sarcoidosis.

First-stage investigations: chest X-ray, spirometry, complete blood count, possibly chest CT in smokers with a persistent cough. A cough in an active smoker for >3 weeks with a change in character or haemorrhagic sputum — urgent investigation (CT, bronchoscopy).

Cough in children: particularities

  • Under 2 years — OTC cough suppressants and mucolytics contraindicated. Saline spray, hydration, honey >1 year.
  • A barking cough with inspiratory stridor — acute laryngitis (croup) — nebulised adrenaline, oral dexamethasone.
  • A paroxysmal cough in fits, followed by an "inspiratory whoop" — pertussis (whooping cough) — diagnosis, isolation, antibiotic.
  • A persistent productive cough in a young child — exclude an inhaled foreign body, cystic fibrosis, immunodeficiency.
  • Bronchiolitis in an infant (RSV) — a viral disease, antibiotics do not help; supportive treatment.

COPD and cough: a category apart

In a patient with COPD, a chronic productive cough is part of the picture. The treatment is not a cough suppressant (you suppress the clearance) but:

  • Quitting smoking — the only intervention that changes the progression.
  • LAMA bronchodilators (tiotropium, glycopyrronium) ± LABA (formoterol, salmeterol) ± an inhaled corticosteroid in the exacerbator phenotype.
  • A chronic mucolytic (NAC 600 mg twice a day, erdosteine) in patients with frequent exacerbations — Cochrane meta-analyses.
  • Pulmonary rehabilitation.
  • Annual influenza vaccination, conjugate and polysaccharide pneumococcal vaccination.

Seasonal allergic cough in Romania

Clear seasons: March-May (birch, beech, poplar), May-July (grasses), August-October (ragweed). A post-nasal drip cough from allergic rhinitis can be the correct diagnosis — treatment: a second-generation antihistamine (loratadine, bilastine) + a nasal spray with mometasone/fluticasone. See also our detailed guide on antihistamines.

Practical cases

  • Adult, a dry cough out of nowhere after the flu, 5 days: butamirate syrup (Sinecod) or levodropropizine (Levopront), hydration, honey and warm tea in the evening.
  • Adult, a productive cough with thick yellow sputum, 3 days, no fever: ambroxol or acetylcysteine (NAC) — thinning; hydration. If fever >3 days or dyspnoea — see a doctor.
  • 4-year-old child with a dry cough at night: honey, head raised, saline nasal spray, butamirate drops as needed over 2 years.
  • Adult with hypertension and a persistent dry cough on enalapril: probably drug-induced — discuss switching to a sartan.
  • COPD patient with an exacerbation: a bronchodilator, short prednisolone, an antibiotic if the sputum is purulent; not a cough suppressant.

Sources

  • Cochrane — OTC medications for acute cough 2014/2024
  • Cochrane — Mucolytic agents for chronic bronchitis or COPD (Poole)
  • EMA — pholcodine withdrawal 2022; ambroxol/bromhexine SJS alert 2015; codeine paediatric restriction 2015
  • ANMDMR — SmPCs for butamirate, ambroxol, acetylcysteine
  • BTS / NICE — chronic cough guidelines
  • GOLD — Global Initiative for Chronic Obstructive Lung Disease (the 2024 strategy)
  • BNF — cough and cold preparations
  • CNAS — lists B and C; CANAMED