Evaluating the Efficacy and Safety of EZC Pak, a 5-Day Combination Echinacea-Zinc-Vitamin C Dose Pack with or without Vitamin D, in the Management of Outpatient Upper Respiratory Infections

Infect Drug Resist. 2023 May 3:16:2561-2572. doi: 10.2147/IDR.S392087. eCollection 2023.


Background: Growing antibiotic resistance is among the most serious threats to public health, with antibiotic misuse considered a leading driver of the problem. One of the largest areas of misuse is in outpatient upper respiratory infections (URIs). The purpose of this research is to evaluate the efficacy of EZC Pak, a combination Echinacea-Zinc-Vitamin C dose pack with or without Vitamin D, on the duration of illness and symptom severity of non-specific URIs as an alternative to antibiotics when none are deemed clinically necessary. A secondary analysis was carried out on patient satisfaction.

Methods: A total of 360 patients across the United States were enrolled and randomized in a double-blind manner across two intervention groups, EZC Pak, EZC Pak+Vitamin D, and one placebo group. The study utilized a smartphone-based app to capture data. Once a participant reported the first URI symptom, they were instructed to take the intervention as directed and complete the daily symptom survey score until their symptoms resolved.

Results: The average EZC Pak participant recovered 1.39 days (90% CI 1.05 to 1.73) faster than the average placebo participant (p=0.017). The average EZC Pak participant reported a 17.43% (90% CI 17.1 to 17.8) lower symptom severity score versus placebo (p=0.029). EZC Pak users reported 2.9 times higher patient satisfaction versus placebo users (p=0.012). The addition of Vitamin D neither benefited nor harmed illness duration or symptom severity.

Conclusion: The findings support the potential use of EZC Pak as an alternative to patient request for antibiotics when none are deemed clinically necessary at the time of initial clinical presentation. The decision to replete vitamin D in the acute phase of URI is an individualized decision left to the patient and their clinician. EZC Pak may play a critical role in improving outpatient URI management and antibiotic stewardship (ClinicalTrials.gov number, NCT04943575).

Keywords: Echinacea; antibiotic stewardship; upper respiratory infection; vitamin D; zinc.

Associated data

  • ClinicalTrials.gov/NCT04943575

Grants and funding

This clinical trial was carried out by Citrus Labs with funding support from PPC Pharmaceuticals. The supply of EZC Pak, EZC Pak+D, and placebo for the trial was provided by PPC Pharmaceuticals.