Summary of COVID-19 NaCl studies
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RCT 50 hospitalized COVID-19 pneumonia patients showing decreased SARS-CoV-2 viral load with nasopharyngeal washes using normal saline 0.9%. In the normal saline group, viral load decreased by 8.9% after 24 hours of treatment, while the control group experienced a 9.7% increase in viral load during the same period. The difference between groups was statistically significant (p=0.005). At follow-up two weeks after hospital discharge, significantly more patients in the normal saline group had negative COVID-19 tests compared to the control group (15 vs 6, p=0.02). No adverse events were reported with the nasal wash intervention. Patients in the control group were older (mean age 56 vs. 45).
Sep 2022, Canadian Respiratory J., https://www.hindawi.com/journals/crj/2022/8794127/, https://c19p.org/pantazopoulos2
RCT 98 outpatients in Brazil, showing faster recovery from cough with inhaled hypertonic saline. Authors note that the effect on coughing may hypothetically be related to a hyperosmotic response influencing the function of different membrane channels and preventing virus entry into the cells; and that the hypertonic solution may increase mucociliary clearance and reduce the destructive inflammatory process in the airways with a decrease in respiratory symptoms.
Sep 2023, J. Clinical Medicine, https://www.mdpi.com/2077-0383/12/18/6075, https://c19p.org/tanni
403 patient NaCl early treatment RCT: 25% improved viral clearance (p=0.11).
RCT 403 children in China with mild/asymptomatic COVID-19, showing significantly faster viral clearance with physiological seawater nasal irrigation.
Sep 2023, World J. Pediatrics, https://link.springer.com/10.1007/s12519-023-00749-z, https://c19p.org/lin8
RCT mechanically ventilated patients in Croatia, showing no significant difference in mortality with saline inhalation. ICU mortality results are from [repozitorij.mefst.unist.hr].
May 2022, Microorganisms, https://www.mdpi.com/2076-2607/10/6/1118, https://c19p.org/delicnacl
Interim analysis of an open-label RCT of 45 non-hospitalized COVID-19 patients showing nasal irrigation with hypertonic saline significantly reduced days to symptom resolution for nasal congestion and headache. The study compared three arms: no intervention, twice-daily irrigation with hypertonic saline (HTS), and hypertonic saline with 1% surfactant (HTSS). Patients using HTS and HTSS experienced resolution of nasal congestion (7-9 days sooner) and headache (7-9 days sooner) than the control group. There was also a trend toward earlier overall symptom resolution (14 days for control vs. 10 days for both intervention groups) and improvement in cough and fatigue, though these did not reach statistical significance. Authors recommend hypertonic saline irrigation as a safe, inexpensive intervention for symptom reduction in COVID-19 patients.
Oct 2020, Int. Forum of Allergy & Rhinology, https://onlinelibrary.wiley.com/doi/full-xml/10.1002/alr.22703, https://c19p.org/kimura2
Prospective study of 61 COVID+ patients showing a significant reduction in viral load and infectivity with a mouthwash containing 0.05% cetylpyridinium chloride (CPC) and 0.05% chlorhexidine digluconate (CHX). Mouthwash containing 0.9% NaCl showed a trend towards lower infectivity. The study only analyzes short-term changes in viral load 30 minutes after treatment.
Mar 2023, J. Dental Research, https://journals.sagepub.com/doi/10.1177/00220345231156415, https://c19p.org/bonnnacl
40 patient NaCl late treatment study: 6% faster recovery (p=0.46) and 24% faster viral clearance (p<0.0001).
Quasi-experimental study of 60 pediatric patients with Omicron COVID-19 infection showing significant reduction in nucleic acid conversion time with nasal saline irrigation compared to routine treatment. Children aged 3-13 years were divided into three groups: routine treatment (Lianhua Qingwen granules), isotonic saline irrigation plus LhQw, and hypertonic saline irrigation plus LhQw. Both saline irrigation groups showed significantly shorter nucleic acid conversion time and increased lymphocyte counts, though no significant differences were observed in fever duration or cough symptoms. Isotonic saline had no adverse events while hypertonic saline caused mild nasal itching (15%) and pain (10%) in some children. Authors suggest that nasal irrigation may promote recovery in children with Omicron infection by physically removing virus particles from the nasal cavity.
Jun 2023, Ear, Nose & Throat J., https://journals.sagepub.com/doi/10.1177/01455613231172337, https://c19p.org/liu27
RCT with 20 saline and 20 control low risk patients in India, showing faster recovery with saline gargling, but no significant difference in viral clearance.
Jul 2022, Indian J. Community Medicine, https://journals.lww.com/ijcm/Fulltext/2022/47020/Impact_of_Steam_Inhalation,_Saline_Gargling,_and.12.aspx, https://c19p.org/chalagerisa
1. Pantazopoulos et al., Nasopharyngeal Wash with Normal Saline Decreases SARS-CoV-2 Viral Load: A Randomized Pilot Controlled Trial
50 patient NaCl late treatment RCT: 85% lower ICU admission (p=0.24), 64% lower need for oxygen therapy (p=0.25), and 51% improved viral clearance (p=0.009).RCT 50 hospitalized COVID-19 pneumonia patients showing decreased SARS-CoV-2 viral load with nasopharyngeal washes using normal saline 0.9%. In the normal saline group, viral load decreased by 8.9% after 24 hours of treatment, while the control group experienced a 9.7% increase in viral load during the same period. The difference between groups was statistically significant (p=0.005). At follow-up two weeks after hospital discharge, significantly more patients in the normal saline group had negative COVID-19 tests compared to the control group (15 vs 6, p=0.02). No adverse events were reported with the nasal wash intervention. Patients in the control group were older (mean age 56 vs. 45).
Sep 2022, Canadian Respiratory J., https://www.hindawi.com/journals/crj/2022/8794127/, https://c19p.org/pantazopoulos2
2. Tanni et al., Efficacy of BREATHOX® Device Inhalation on Acute Symptoms Associated with COVID-19 (BREATH Study): A Randomized Pilot Clinical Trial
98 patient NaCl early treatment RCT: 75% lower hospitalization (p=0.34) and 10% worse recovery (p=0.7).RCT 98 outpatients in Brazil, showing faster recovery from cough with inhaled hypertonic saline. Authors note that the effect on coughing may hypothetically be related to a hyperosmotic response influencing the function of different membrane channels and preventing virus entry into the cells; and that the hypertonic solution may increase mucociliary clearance and reduce the destructive inflammatory process in the airways with a decrease in respiratory symptoms.
Sep 2023, J. Clinical Medicine, https://www.mdpi.com/2077-0383/12/18/6075, https://c19p.org/tanni
403 patient NaCl early treatment RCT: 25% improved viral clearance (p=0.11).
RCT 403 children in China with mild/asymptomatic COVID-19, showing significantly faster viral clearance with physiological seawater nasal irrigation.
Sep 2023, World J. Pediatrics, https://link.springer.com/10.1007/s12519-023-00749-z, https://c19p.org/lin8
4. Delić et al., Effects of Different Inhalation Therapy on Ventilator-Associated Pneumonia in Ventilated COVID-19 Patients: A Randomized Controlled Trial
94 patient NaCl ICU RCT: 26% lower mortality (p=0.09).RCT mechanically ventilated patients in Croatia, showing no significant difference in mortality with saline inhalation. ICU mortality results are from [repozitorij.mefst.unist.hr].
May 2022, Microorganisms, https://www.mdpi.com/2076-2607/10/6/1118, https://c19p.org/delicnacl
5. Kimura et al., Interim analysis of an open‐label randomized controlled trial evaluating nasal irrigations in non‐hospitalized patients with coronavirus disease 2019
31 patient NaCl late treatment RCT: 29% faster recovery (p=0.16).Interim analysis of an open-label RCT of 45 non-hospitalized COVID-19 patients showing nasal irrigation with hypertonic saline significantly reduced days to symptom resolution for nasal congestion and headache. The study compared three arms: no intervention, twice-daily irrigation with hypertonic saline (HTS), and hypertonic saline with 1% surfactant (HTSS). Patients using HTS and HTSS experienced resolution of nasal congestion (7-9 days sooner) and headache (7-9 days sooner) than the control group. There was also a trend toward earlier overall symptom resolution (14 days for control vs. 10 days for both intervention groups) and improvement in cough and fatigue, though these did not reach statistical significance. Authors recommend hypertonic saline irrigation as a safe, inexpensive intervention for symptom reduction in COVID-19 patients.
Oct 2020, Int. Forum of Allergy & Rhinology, https://onlinelibrary.wiley.com/doi/full-xml/10.1002/alr.22703, https://c19p.org/kimura2
6. Bonn et al., Efficacy of a Mouthwash Containing CHX and CPC in SARS-CoV-2–Positive Patients: A Randomized Controlled Clinical Trial
60 patient NaCl early treatment study: 72% improved viral clearance (p=0.1).Prospective study of 61 COVID+ patients showing a significant reduction in viral load and infectivity with a mouthwash containing 0.05% cetylpyridinium chloride (CPC) and 0.05% chlorhexidine digluconate (CHX). Mouthwash containing 0.9% NaCl showed a trend towards lower infectivity. The study only analyzes short-term changes in viral load 30 minutes after treatment.
Mar 2023, J. Dental Research, https://journals.sagepub.com/doi/10.1177/00220345231156415, https://c19p.org/bonnnacl
40 patient NaCl late treatment study: 6% faster recovery (p=0.46) and 24% faster viral clearance (p<0.0001).
Quasi-experimental study of 60 pediatric patients with Omicron COVID-19 infection showing significant reduction in nucleic acid conversion time with nasal saline irrigation compared to routine treatment. Children aged 3-13 years were divided into three groups: routine treatment (Lianhua Qingwen granules), isotonic saline irrigation plus LhQw, and hypertonic saline irrigation plus LhQw. Both saline irrigation groups showed significantly shorter nucleic acid conversion time and increased lymphocyte counts, though no significant differences were observed in fever duration or cough symptoms. Isotonic saline had no adverse events while hypertonic saline caused mild nasal itching (15%) and pain (10%) in some children. Authors suggest that nasal irrigation may promote recovery in children with Omicron infection by physically removing virus particles from the nasal cavity.
Jun 2023, Ear, Nose & Throat J., https://journals.sagepub.com/doi/10.1177/01455613231172337, https://c19p.org/liu27
8. Chalageri et al., Impact of steam inhalation, saline gargling, and povidone-iodine gargling on clinical outcome of COVID-19 patients in Bengaluru, Karnataka: A randomized control trial
40 patient NaCl early treatment RCT: 43% improved recovery (p=0.0004).RCT with 20 saline and 20 control low risk patients in India, showing faster recovery with saline gargling, but no significant difference in viral clearance.
Jul 2022, Indian J. Community Medicine, https://journals.lww.com/ijcm/Fulltext/2022/47020/Impact_of_Steam_Inhalation,_Saline_Gargling,_and.12.aspx, https://c19p.org/chalagerisa
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