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

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