Nasal and oral rinses to reduce COVID-19 viral load

SARS-Cov-2 (COVID-19) Nasal Pharyngeal and Oral Pharyngeal Wash (SNOW) Trial

Phase2; Phase3 Interventional Milton S. Hershey Medical Center · NCT04802408

This study is testing if using a baby shampoo nasal wash and Listerine mouth rinse can help adults recently diagnosed with COVID-19 lower their viral load and reduce the risk of spreading the virus.

Quick facts

PhasePhase2; Phase3
Study typeInterventional
Enrollment200 (estimated)
Ages18 Years to 65 Years
SexAll
SponsorMilton S. Hershey Medical Center Academic / other
Locations2 sites (Hershey, Pennsylvania and 1 other locations)
Trial IDNCT04802408 on ClinicalTrials.gov

What this trial studies

This trial investigates the effectiveness of a combined intervention using nasal washes with a 1% baby shampoo solution and oral gargles with Listerine Antiseptic® in adults recently diagnosed with SARS-CoV-2 infection. Participants will be compared to a control group using normal saline for their rinses. The goal is to determine if these rinses can significantly reduce the viral load in the naso-oropharynx, potentially lowering the risk of transmission. The study aims to provide a safe, low-cost method for managing COVID-19 symptoms and reducing viral spread.

Who should consider this trial

Good fit: Ideal candidates are adults aged 18-65 who have recently tested positive for SARS-CoV-2 and are currently in isolation.

Not a fit: Patients who have a history of nasal or sinus surgery or those requiring inpatient care for COVID-19 will not benefit from this study.

Why it matters

Potential benefit: If successful, this intervention could provide a simple and effective method for reducing COVID-19 viral load and transmission.

How similar studies have performed: While similar approaches have shown promise in vitro, this specific combination of interventions is novel and has not been extensively tested in clinical settings.

Eligibility criteria

Show full inclusion / exclusion criteria
Inclusion Criteria:

1. A first-time positive test for SARS-CoV-2 infection within 5 days of enrollment
2. Adults who are ≥18 -65 years of age
3. Currently in isolation
4. Symptomatic or asymptomatic from SARS-CoV-2

Exclusion Criteria:

1. History of nasal or sinus surgery
2. Non-English speaking
3. Lack of electronic device (computer, mobile phone etc.) on which to access an app for study data collection.
4. Adults that need inpatient care for COVID-19 or any of its complications.
5. Adults that give a history of being unable to tolerate gargles or nasal washes.
6. Adults who do not give informed consent for study participation.
7. History of a Covid vaccine booster
8. A history of use of nasal or oral washes after SARS-CoV-2 test sample collection.
9. Prisoners
10. Adults that give history of current pregnancy (NO KNOWN CONTRAINDICATION TO PREGNANCY)
11. History of monoclonal antibody treatment
12. History of or current molnupiravir treatment

Where this trial is running

Hershey, Pennsylvania and 1 other locations

Study contacts

How to participate

  1. Review the eligibility criteria above with your treating physician.
  2. Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
  3. Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.
Conditions Covid19SARS-CoV InfectionCovid 19SARS-CoV-2Viral LoadNasal RinseOral Rinse
Last reviewed 2026-06-13 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.