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Completed Phase 4 Interventional

To Determine if Diphenhydramine Works for Nasal Congestion at Two Different Doses

ClinicalTrials.gov ID: NCT00648973

Public ClinicalTrials.gov record NCT00648973. Field values are reproduced from the official study page; the official ClinicalTrials.gov record remains the source of truth for eligibility, enrollment, and contact information.

ClinicalTrials.gov public records Last synced Jul 21, 2026, 6:52 PM EDT

Data is sourced from official ClinicalTrials.gov public API records. Always review the official ClinicalTrials.gov record for the latest information.

Official title

Evaluation of Nasal Congestion Clinical Efficacy for Diphenhydramine 25 mg and Diphenhydramine 50 mg in Seasonal Allergic Rhinitis: a Randomized, Double-blind, Placebo and Pseudoephedrine Controlled Study

Study identification

NCT ID
NCT00648973
Recruitment status
Completed
Study type
Interventional
Phase
Phase 4
Lead sponsor
Johnson & Johnson Consumer and Personal Products Worldwide
Industry
Enrollment
1,021 participants

Conditions and interventions

Interventions

  • Diphenhydramine 50 mg Drug
  • Diphenhydramine 25 mg Drug
  • Pseudoephedrine 120 mg Drug

Drug

Eligibility (public fields only)

Age range
12 Years to 65 Years
Sex
All
Healthy volunteers
Healthy volunteers not accepted

This page does not interpret eligibility. Detailed inclusion and exclusion criteria are on the official ClinicalTrials.gov record.

Study timeline

Start date
Oct 31, 2006
Primary completion
Apr 30, 2007
Completion
Apr 30, 2007
Last update posted
Aug 21, 2011

2006 – 2007

United States locations

U.S. sites
12
U.S. states
1
U.S. cities
7
Facility City State ZIP Site status
Benchmark Research - Austin Austin Texas 78705
Allergy and Asthma Associates Austin Texas 78731
Lovelace Scientific Resources Austin Texas 78759
Allergy/Immunology Research Center of North Texas Dallas Texas 75230
Kerrville Research Associates Kerrville Texas 78028
Central Texas Health Research New Braunfels Texas 78130
Benchmark Research - San Angelo San Angelo Texas 76904
Sun Research Institute San Antonio Texas 78205
Biogenics Research Institute San Antonio Texas 78229
Diagnostics Research Group San Antonio Texas 78229
Sylvana Research Associates San Antonio Texas 78229
Allergy Asthma Research Institute Waco Texas 76712

Site contact phone numbers, emails, and investigator names are intentionally not displayed here. Open the official ClinicalTrials.gov record for site contact information.

About this trial record page

What this page shows
Public field values for ClinicalTrials.gov record NCT00648973, including study identification, conditions, interventions, eligibility (age, sex, healthy volunteer), timeline, and U.S. site list.
What this page does not do
No medical advice, eligibility judgments, treatment recommendations, study quality scoring, or AI-generated medical summaries. No site contact phone numbers, emails, or investigator names.
Where the data comes from
Sourced from the official ClinicalTrials.gov public API. The official record is the source of truth.
Last refresh
Last update posted Aug 21, 2011 · Synced Jul 21, 2026

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Open the official record

The complete protocol, eligibility criteria, and contact information for NCT00648973 live on ClinicalTrials.gov.

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