Are macrolide antibiotics effective in chronic idiopathic cough?

Macrolide antibiotics in the treatment of chronic idiopathic cough: a randomised double-blind, placebo-controlled, parallel-group trial

Status

Active, not recruiting

Phases

Phase 3

Study type

Interventional

Source

ISRCTN

Registry ID

ISRCTN75749391

Enrollment

Registered

2009-09-23

Start date

2009-07-01

Completion date

Unknown

Last updated

2016-10-17

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Chronic idiopathic cough Signs and Symptoms Cough

Interventions

Azithromycin 500 mg for 3 days followed by 250 mg three times weekly for 7 weeks or matching placebo treatment regimen.

Eligibility

Sex/Gender

All

Inclusion criteria

Inclusion criteria: Non-smoking subjects aged 18 to 80 years (either sex) with idiopathic cough for at least 2 months

Exclusion criteria

Exclusion criteria: 1. Active smoking or smoking history in excess of 20 pack years 2. Non-idiopathic cough or other major co-morbidity including abnormal liver function tests 3. Medication known to interact with azithromycin

Design outcomes

Primary

Measure	Time frame
Leicester Cough Questionnaire score, measured after 8 weeks' treatment with azithromycin or placebo	—

Secondary

Measure	Time frame
1. Cough severity score 2. Adverse effects Measured at study visits after 4 weeks, 8 weeks and 12 weeks	—

Countries

United Kingdom

Outcome results

None listed

Source: ISRCTN (via WHO ICTRP) · Data processed: Mar 14, 2026