Echinacea Versus Placebo Effect in Common Cold (Physician Echinacea Placebo) (PEP)

This study has been completed.
Information provided by (Responsible Party):
University of Wisconsin, Madison Identifier:
First received: July 31, 2003
Last updated: December 3, 2014
Last verified: December 2014

July 31, 2003
December 3, 2014
September 2003
August 2008   (final data collection date for primary outcome measure)
Duration and severity of illness, as assessed by the Wisconsin Upper Respiratory Symptom Survey (WURSS-21) [ Time Frame: twice daily during illness ] [ Designated as safety issue: No ]
Not Provided
Complete list of historical versions of study NCT00065715 on Archive Site
  • SF-8 general health-related quality of life [ Time Frame: daily during illness ] [ Designated as safety issue: No ]
  • perceived stress PSS-4 [ Time Frame: daily during illness ] [ Designated as safety issue: No ]
  • optimism LOT [ Time Frame: two days after enrollment ] [ Designated as safety issue: No ]
  • patient satisfaction CARE [ Time Frame: after doctor patient interaction ] [ Designated as safety issue: Yes ]
  • feeling thermometer - EuroQol VAS [ Time Frame: daily during illness ] [ Designated as safety issue: No ]
  • IL-8 (inflammatory cytokine)from nasal wash [ Time Frame: 2 days after enrollment ] [ Designated as safety issue: No ]
  • neutrophil count from nasal wash [ Time Frame: two days after enrollment ] [ Designated as safety issue: No ]
Not Provided
Not Provided
Not Provided
Echinacea Versus Placebo Effect in Common Cold (Physician Echinacea Placebo)
Placebo: Physician or Pill? A Randomized Trial in a Common Cold Model Funded by NIH NCCAM Under RFA "The Placebo Effect in Clinical Practice"

The design and interpretation of randomized trials is intimately connected to the use of "placebo". The nature and magnitude of placebo effects, however, is very poorly understood. This study will assess and compare placebo effects and physician interaction effects within a community-acquired common cold model. The goal of this study is to assess two kinds of placebo affects and how physician interaction effects;

  1. The effect of receiving blinded placebo, compared to no treatment; and
  2. The effect of receiving open-label active Echinacea treatment compared to blinded active treatment.

As per Brief Summary

Phase 3
Allocation: Randomized
Endpoint Classification: Efficacy Study
Intervention Model: Parallel Assignment
Masking: Double Blind (Subject, Caregiver, Investigator, Outcomes Assessor)
Primary Purpose: Treatment
Common Cold
  • Dietary Supplement: Echinacea
    Echinacea phytochemical profile Each tablet is comprised of the equivalent of 1275 mg of echinacea root, as follows: A) Echinacea purpurea - 675 mg root yields 112.5 mg dried extract, standardized to contain 2.1mg alkamides. B) Echinacea angustifolia - 600 mg root yields 150 mg dried extract, standardized to contain 2.0 mg alkamides. Each batch of tablets is analyzed by Reversed Phase - High Peformance Liquid Chromatography to determine the levels of alkamides and caffeic derivatives present. Caffeic acid derivative levels are typically as follows: caftaric acid = 0.5 to 2.0 mg/tablet; cichoric acid = 3.4 to 8.5 mg/tablet; chlorogenic acid = < 0.5 mg/tablet; dicaffeoyl quinic acids (including cynarin) = 0.7 to 2.0 mg/tablet; echinacoside = 1.0 to 1.7 mg/tablet
  • Other: Blinded placebo
    Blinded placebo - Coated tablet
  • No Intervention: A
    No pills
  • Placebo Comparator: B
    Blinded placebo
    Intervention: Other: Blinded placebo
  • Experimental: C
    Echinacea - Blinded
    Intervention: Dietary Supplement: Echinacea
  • Experimental: D
    Echinacea - Unblinded, Open Label
    Intervention: Dietary Supplement: Echinacea

*   Includes publications given by the data provider as well as publications identified by Identifier (NCT Number) in Medline.
April 2013
August 2008   (final data collection date for primary outcome measure)

Inclusion criteria:

  • Suspected or known cold
  • At least one of the following cold symptoms:

nasal discharge, nasal congestion, sneezing, or sore throat

  • Enrolled in school, for children 12 to 17 years of age

Exclusion criteria:

  • Pregnancy;
  • Symptom duration > 36 hrs
  • Concurrent use of antibiotics, antivirals, nasal steroids, decongestants or antihistamines;
  • Anticipated need for symptom-relieving meds during cold
  • Autoimmune/deficiency disease
  • History of allergic rhinitis with current eye itching/sneezing
  • History of asthma w/current cough/SOB
  • Prior study entry
  • Allergy to Echinacea
12 Years and older
Contact information is only displayed when the study is recruiting subjects
United States
R01 AT001428, R01AT001428, BarrettB
University of Wisconsin, Madison
University of Wisconsin, Madison
  • National Center for Complementary and Integrative Health (NCCIH)
  • National Heart, Lung, and Blood Institute (NHLBI)
Principal Investigator: Bruce Barrett, MD PhD University of Wisconsin, Madison
University of Wisconsin, Madison
December 2014

ICMJE     Data element required by the International Committee of Medical Journal Editors and the World Health Organization ICTRP