Cough Reflex Sensitivity
Conditions
Keywords
cough, cough reflex, capsaicin, diphenhydramine, phenylephrine, dextromethorphan, placebo
Brief summary
The purpose of this study is to evaluate the antitussive (cough-suppressing) effects of two liquid medications: a combination of diphenhydramine and phenylephrine in a naturally cocoa flavoring, and, dextromethorphan syrup, compared with placebo.
Interventions
DRUGplacebo; dextromethorphan; diphenhydramine/phenylephrine/cocoa
placebo; dextromethorphan 30 mg; diphenhydramine 25 mg and phenylephrine 10 mg
DRUGdiphenhydramine/phenylephrine/cocoa; dextromethorophan; placebo
diphenhydramine 25 mg and phenylephrine 10 mg; dextromethorphan 30 mg; placebo.
DRUGdiphenhydramine/phenylephrine/cocoa; placebo; dextromethorphan
diphenhydramine 25 mg and phenylephrine 10 mg; placebo; dextromethorphan 30 mg.
DRUGdextromethorphan; diphenhydramine/phenylephrine/cocoa; placebo
dextromethorphan 30 mg; diphenhydramine 25 mg and phenylephrine 10 mg; placebo
DRUGdextromethorophan; placebo; diphenhydramine/phenylephrine/cocoa
dextromethorphan 30 mg; placebo; diphenhydramine 25 mg and phenylephrine 10 mg
DRUGplacebo; diphenhydramine/phenylephrine/cocoa; dextromethorphan
placebo; diphenhydramine 25 mg and phenylephrine 10 mg; dextromethorphan 30 mg
Sponsors
Montefiore Medical Center
Study design
Allocation
RANDOMIZED
Intervention model
CROSSOVER
Primary purpose
TREATMENT
Masking
DOUBLE (Subject, Investigator)
Eligibility
Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
No
Inclusion criteria
* healthy adult nonsmokers * onset of acute, viral upper respiratory tract infection (common cold) within 72 hours of enrollment
Exclusion criteria
* smokers * history of asthma or other respiratory disorders
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Change in Cough Reflex Sensitivity to Capsaicin | 2 hours after study drug administration | increase in C5 (decrease in cough reflex sensitivity). Capsaicin cough challenge involves subjects breathing in incremental doubling concentrations of aerosolized capsaicin, 1 minute apart, until the concentration of capsaicin (micromolar) inducing 5 or more coughs (C5) is reached. |
Countries
United States
Participant flow
Participants by arm
| Arm | Count |
|---|---|
| Diphenhydramine/Phenylephrine/Cocoa, Dextromethorphan,Placebo Diphenhydramine 25 mg, phenylephrine 10 mg, in naturally-flavored cocoa syrup; dextromethorphan; placebo.
Intervention: capsaicin cough challenge testing 2 hours after study drug ingestion.
Phenylephrine: 10 mg dose phenylephrine
Diphenhydramine: 25 mg dose diphenhydramine
Dextromethorphan: 30 mg dose dextromethorphan | 22 |
| Total | 22 |
Baseline characteristics
| Characteristic | Diphenhydramine/Phenylephrine/Cocoa, Dextromethorphan,Placebo |
|---|---|
| Age, Categorical <=18 years | 0 Participants |
| Age, Categorical >=65 years | 0 Participants |
| Age, Categorical Between 18 and 65 years | 22 Participants |
| Sex: Female, Male Female | 16 Participants |
| Sex: Female, Male Male | 6 Participants |
Adverse events
| Event type | EG000 affected / at risk | EG001 affected / at risk | EG002 affected / at risk |
|---|---|---|---|
| deaths Total, all-cause mortality | — / — | — / — | — / — |
| other Total, other adverse events | 0 / 22 | 0 / 22 | 0 / 22 |
| serious Total, serious adverse events | 0 / 22 | 0 / 22 | 0 / 22 |
Outcome results
Primary
Change in Cough Reflex Sensitivity to Capsaicin
increase in C5 (decrease in cough reflex sensitivity). Capsaicin cough challenge involves subjects breathing in incremental doubling concentrations of aerosolized capsaicin, 1 minute apart, until the concentration of capsaicin (micromolar) inducing 5 or more coughs (C5) is reached.
Time frame: 2 hours after study drug administration
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Diphenhydramine/Phenylephrine/Cocoa | Change in Cough Reflex Sensitivity to Capsaicin | 0.97 log C5 (uM) | Standard Error 0.16 |
| Dextromethorphan | Change in Cough Reflex Sensitivity to Capsaicin | 0.80 log C5 (uM) | Standard Error 0.18 |
| Placebo | Change in Cough Reflex Sensitivity to Capsaicin | 0.57 log C5 (uM) | Standard Error 0.16 |