Skip to main content
OpenTrials
Completed

NCT Number: NCT04421092

Efficacy of SLN Block for Chronic Cough

This is a research study to find out if superior laryngeal nerve blocks are an effective way to reduce cough when compared to placebo (a substance without any medical value). Eligibility for the study include the following: age >18, cough history suggestive that the nerve to the voice box is overactive, non-smoker, Patients will be followed over time and assigned to either the treatment or placebo group at random. The treatment would be four superior laryngeal nerve blocks and the placebo would be four saline injections (the inactive substance). Study team will measure if the injection improved cough and ask patients to keep a log of symptoms and fill out questionnaires at each visit. After the four injections, patients will follow up in 3 months to see if cough has returned and if so, how severe the cough is.

Completed

Looking for future studies?

Notify Me

Key information

Conditions

Cough Chronic Cough Neurogenic Cough Pathological Conditions, Signs and Symptoms Respiration Disorders Respiratory Tract Diseases Signs and Symptoms Signs and Symptoms, Respiratory Superior Laryngeal Nerve Block

Age range

18 year and older

Sex eligibility

All sexes

Study type

Interventional

Phase

Phase 3

Primary location

Medical University of South Carolina

Charleston, South Carolina, 29403, United States

Who can participate

Healthy volunteers accepted: Yes

Only the study team can determine whether someone qualifies for participation.

Inclusion criteria

  • History consistent with neurogenic cough
  • Exclusion of other etiologies (see exclusion criteria)
  • Age ≥ 18

Exclusion criteria

  • Current neuromodulating medication use
  • Untreated other etiologies of cough:

Current smoker Current ACE/ARB use Abnormal PFTs within 6 months Uncontrolled OSA Abnormal CXR within 6 months RSI > 13 or RFS >11 AND workup positive for GERD (esophagram, 24-hour pH probe, manometry, EGD)

Treatment and study plan

Superior laryngeal nerve block

Procedure

Injection of either the steroid-lidocaine mixture or placebo through the skin around where the superior laryngeal nerve is located on the neck. The procedure lasts 5 minutes and is done in the clinic.

Other names: Injection of steroid-lidocaine mixture vs. placebo (saline)

Injection of placebo (saline)

Procedure

Superior laryngeal nerve block using 1mL of saline as the injection.

Other names: 1mL of saline as the injection

Injection of steroid-lidocaine mixture

Procedure

Superior laryngeal nerve block using 1mg 1:1 triamcinolone 40mg: 1% lidocaine with 1:200000 epinephrine as the injection.

Other names: 1mg 1:1 triamcinolone 40mg: 1% lidocaine with 1:200000 epinephrine as the injection.

Primary outcomes

  1. Change in Cough Severity

    Time frame: Change from Baseline to 3 months

    Patient will complete the Leicester Cough Questionnaire at each visit. This is a validated survey that measures 3 domains (physical, psychological and social). The total score range is 3-21 and domain scores range from 1-7; a higher score indicates a better quality of life.

Secondary outcomes

  1. Subjective Improvement in Cough

    Time frame: Baseline, 1-4 weeks post-injection, and 3 months post-treatment

    Improvement was defined as a 'yes' response at any time point during the study (1-4 weeks or 3 months post-treatment). The reported value reflects the total number of participants who reported improvement at any time point.

  2. Summed Daily Change in Subjective Cough Severity

    Time frame: Daily for 3 months post-injection

    Participants rate cough severity on a 0-15 visual analogue scale. Scores are recorded daily and analyzed using regression. Higher scores indicate greater severity. VAS is a 0-15 scale completed daily by participants.

    Severity is measured using a ruler to determine percentage along the scale. Scores were analyzed using regression models to assess trends over time.

Sponsors and collaborators

Lead sponsor

Medical University of South Carolina

Other

Registry information

Official study title

Efficacy of Superior Laryngeal Nerve Block for Chronic Cough

Important dates

Study start
2020
Primary completion
2022
Study completion
2022
First posted
Jun 9, 2020
Registry last updated
Oct 23, 2025

OpenTrials presents study information sourced from ClinicalTrials.gov. The official registry record should be consulted for the latest information.

View the official ClinicalTrials.gov record (opens in a new tab)

This listing is for discovery and informational purposes only. It is not medical advice, does not guarantee that a study is recruiting, and does not determine eligibility. Contact the study team and a qualified healthcare professional when considering participation.

Related clinical trials

Published trials that share one or more normalized conditions with this study.