What is protracted bacterial bronchitis in children?

Protracted bacterial bronchitis, or PBB, is a common cause of chronic wet cough in children. It is usually considered when a wet cough lasts more than four weeks, there are no clear signs of another cause, and the cough resolves with an appropriate clinician-prescribed antibiotic course.

Protracted Bacterial Bronchitis in Children: Chronic Wet Cough Guide

Q: Is PBB the same as asthma?

No. PBB usually causes a wet or phlegmy cough, while asthma more often has wheeze, chest tightness, exercise symptoms, night symptoms and trigger patterns. Some children can have more than one problem, so persistent wet cough should not be labelled asthma without review.

Q: Does recurrent PBB matter?

Yes. Recurrent PBB or cough that does not improve as expected needs review for bronchiectasis and underlying causes such as aspiration, airway abnormality, cystic fibrosis, primary ciliary dyskinesia or immune problems.

Q: When is wet cough urgent?

Urgent in-person care is needed for chest indrawing, blue lips, drowsiness, low oxygen, severe breathlessness, choking history, coughing blood, dehydration, severe chest pain or a child who looks very unwell.

A child with protracted bacterial bronchitis often looks well between coughing spells, but the cough is wet, daily and stubborn. The goal is not to suppress the cough. The goal is to recognise the pattern, treat appropriately when PBB fits, and make sure recurrent or non-resolving wet cough is not hiding a bigger airway problem.

Red flags first

A wet cough is not always safe to watch.

Chest indrawing, grunting, blue lips, drowsiness, exhaustion or low oxygen needs urgent in-person care.
Choking history, sudden cough, one-sided wheeze or sudden noisy breathing should not be labelled PBB without urgent assessment.
Fast breathing with fever, severe chest pain, dehydration, poor feeding or a child who looks very unwell should not wait online.
Coughing blood, poor growth, clubbing, recurrent pneumonia or wet cough from early infancy needs structured specialist review.
Do not use video consultation as the first step for acute respiratory distress or rapid worsening.

Chronic wet cough board

PBB care works best when parents connect wet cough duration, red flags, antibiotic response, recurrence and cause-finding.

सह

The cough is wet because mucus is present.

PBB is usually about ongoing airway infection and mucus, not a habit cough, not ordinary post-viral throat tickle and not asthma alone.

Emergency signsLow oxygen, chest indrawing, blue lips or drowsiness needs urgent care.

Wet daily coughParents often describe rattly, phlegmy cough that does not fully clear.

Four-week clueChronic cough in children is commonly defined as cough lasting more than four weeks.

Response mattersCough resolution after appropriate antibiotics supports the PBB diagnosis.

Recurrence mattersRepeated episodes or incomplete response need bronchiectasis and cause review.

Cause findingAspiration, airway anomaly, PCD, CF and immune problems may need review.

A safer PBB conversation separates common prolonged wet cough from red-flag chronic lung disease.

Check 01

Is the cough truly wet?

A wet, rattly or phlegmy cough most days is different from a dry tickle, habit cough or throat-clearing pattern.

Check 02

Has it lasted more than four weeks?

PBB is usually considered in chronic wet cough, not every cold-related cough in the first few days.

Check 03

Are there specific warning clues?

Poor growth, clubbing, recurrent pneumonia, choking, early infancy onset, blood, focal chest signs or immune concerns change the pathway.

Check 04

Did it fully resolve?

Partial improvement is not the same as resolution. Families should track whether the wet cough actually disappeared.

Check 05

Has it returned?

Recurrent PBB, repeated antibiotic courses or non-response should prompt deeper review rather than endless repeat prescriptions.

Parent tip: Record cough duration, wet/dry quality, fever, sleep impact, sputum if any, choking history, previous antibiotics, response timeline, X-rays, growth chart, school absence and any wheeze or asthma medicines.

Original parent-guide visual by Together We Breathe · © 2026. Designed to explain PBB conversations for families. It does not replace prescribing, examination, cultures, imaging, emergency care or specialist follow-up.

What PBB is — and what it is not.

Protracted bacterial bronchitis means there is a prolonged bacterial infection and inflammation inside the larger airways, causing a chronic wet cough. It is usually a clinical diagnosis made after careful review of the cough pattern and exclusion of other warning clues.

It is not just “allergy cough,” because the cough is typically wet and mucus-filled.
It is not the same as asthma, although some children can have both conditions.
It is not diagnosed from mucus colour alone.
It is not a reason to start random leftover antibiotics at home.
It is not something to ignore when it keeps coming back.

Clues parents may notice.

Wet cough most days

The cough sounds phlegmy, rattly or chesty, and it persists beyond the usual cold timeline.

More than four weeks

PBB is usually considered when wet cough becomes chronic, commonly beyond four weeks in children.

Otherwise active child

Many children with PBB can look well, play and have no fever, which is why the cough pattern matters.

Poor response to cough syrup

Suppressants, mucolytics or repeated cold medicines do not address airway infection when PBB is the issue.

Antibiotic response

Resolution after an appropriate clinician-prescribed antibiotic course supports the diagnosis; incomplete response needs review.

Recurrent episodes

Multiple episodes in a year or persistent wet cough after treatment should prompt deeper cause-finding.

How clinicians think through diagnosis.

Confirm that the cough is wet or productive rather than dry, barking or habit-like.
Check duration, often more than four weeks in children.
Look for specific cough pointers: poor growth, clubbing, recurrent pneumonia, choking, aspiration, blood, focal chest signs, immune concerns or symptoms from early infancy.
Review asthma and allergy clues without assuming every cough is asthma.
Consider chest X-ray, cultures, spirometry, bronchoscopy, CT or specialist tests only when the pattern or red flags suggest they are needed.
Assess response after appropriate treatment rather than assuming partial improvement is enough.

Key message

PBB is treatable, but repeated PBB is a warning signal.

A single clinician-directed treatment course may resolve the cough. But recurrent episodes, incomplete response, repeated pneumonia, poor growth, choking history or abnormal examination should shift the conversation toward bronchiectasis risk and underlying causes.

Why antibiotics should not be used blindly.

The diagnosis must fit: chronic wet cough without specific signs of another cause.
The right antibiotic choice depends on local practice, allergy history, prior antibiotics, severity and clinician assessment.
Short or inappropriate antibiotic exposure can confuse the picture without fully resolving the airway infection.
Repeated courses without review may delay diagnosis of bronchiectasis, aspiration, airway abnormality, cystic fibrosis, primary ciliary dyskinesia or immune problems.
Side effects, resistance risk and wrong-diagnosis risk matter.
Parents should not use leftover antibiotics or another child’s prescription.

When recurrent PBB needs deeper review.

More than one or two episodes, or repeated wet cough requiring antibiotics.
Wet cough that does not fully disappear after clinician-directed treatment.
More than three PBB-like episodes in a year.
Recurrent pneumonia, abnormal chest X-ray or focal chest signs.
Poor growth, clubbing, fatigue, exercise limitation or school absence.
Symptoms from early infancy, neonatal breathing problems, chronic nasal symptoms or ear disease suggesting PCD.
Greasy stools, poor weight gain, salty sweat concerns or family history suggesting cystic fibrosis.
Choking, cough with feeds, vomiting with cough or neurological/swallow concerns suggesting aspiration.

What not to do blindly.

Do not suppress a chronic wet cough for weeks without assessing why mucus is present.
Do not label every wet cough as asthma if wheeze, triggers and response do not fit.
Do not repeat antibiotics again and again without follow-up and cause-finding.
Do not use leftover antibiotics or stop early because the cough sounds slightly better.
Do not ignore recurrent pneumonia, poor growth, clubbing, blood in sputum or focal chest findings.
Do not miss choking or aspiration clues, especially sudden onset or cough with feeds.
Do not delay specialist review if wet cough persists or keeps returning.
Do not use video consultation for acute respiratory distress, low oxygen or a child who appears seriously unwell.

Medical trust note

How this page was prepared.

This parent guide is written in simple language and reviewed for clinical safety by Dr. Antar Patel. It uses pediatric chronic wet cough, PBB, CHEST, ERS, ATS patient education and bronchiectasis-risk source families. It avoids copied copyrighted figures, does not provide antibiotic dosing, and is for education only.

Frequently asked questions.

01What is protracted bacterial bronchitis?

PBB is a common cause of chronic wet cough in children. It is usually considered when wet cough lasts more than four weeks, there are no clear signs of another cause, and the cough resolves with appropriate clinician-prescribed antibiotics.

02Is PBB the same as asthma?

No. PBB usually causes wet, phlegmy cough. Asthma more often has wheeze, chest tightness, exercise symptoms, trigger patterns and reliever response. Some children can have both.

03Does every wet cough need antibiotics?

No. Short wet coughs during viral infections are common. Antibiotics should be clinician-directed when the pattern fits and safety signs have been reviewed.

04Why does recurrent PBB matter?

Recurrent PBB can be associated with bronchiectasis risk or an underlying reason mucus is not clearing well. Repeated episodes need follow-up rather than endless repeat prescriptions.

05What if the cough only partly improves?

Partial improvement is not the same as resolution. Persistent wet cough after treatment should prompt review of the diagnosis, treatment fit, adherence and possible underlying causes.

06When is wet cough urgent?

Urgent care is needed for chest indrawing, blue lips, drowsiness, low oxygen, severe breathlessness, choking history, coughing blood, dehydration, severe chest pain or a very unwell child.

Clinical source family

Guidance used while writing this page.

These external references are shared for transparency. They do not replace clinical assessment and do not imply endorsement of this website.