Summary of COVID-19 NaCl studies
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RCT 379 mild COVID-19 cases showing significantly lower prevalence and severity of olfactory and gustatory dysfunction with budesonide nasal spray, chlorhexidine mouthwash, and saline nasal irrigation. The control group received no intervention, the saline group received saline nasal irrigation plus saline nasal spray and mouthwash, and the drug group received saline nasal irrigation plus budesonide nasal spray and chlorhexidine mouthwash. Saline nasal irrigation plus nasal spray and mouthwash were administered once and four times daily, respectively. Both treatment groups had significantly lower prevalence and severity olfactory and gustatory dysfunction. Prevalence was lower for the drug vs. saline group, without statistical significance.
Nov 2023, QJM: An Int. J. Medicine, https://academic.oup.com/qjmed/advance-article/doi/10.1093/qjmed/hcad262/7439598, https://c19p.org/jingnaclnacl
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/tanninacl
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/lin8nacl
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/delicnaclnacl
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/kimura2nacl
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/bonnnaclnacl
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/chalagerisanacl
1. Jing et al., Effective early strategy to prevent olfactory and gustatory dysfunction in COVID-19: a randomized controlled trial
260 patient NaCl early treatment RCT: 71% lower progression (p<0.0001) and 97% lower severe cases (p<0.0001).RCT 379 mild COVID-19 cases showing significantly lower prevalence and severity of olfactory and gustatory dysfunction with budesonide nasal spray, chlorhexidine mouthwash, and saline nasal irrigation. The control group received no intervention, the saline group received saline nasal irrigation plus saline nasal spray and mouthwash, and the drug group received saline nasal irrigation plus budesonide nasal spray and chlorhexidine mouthwash. Saline nasal irrigation plus nasal spray and mouthwash were administered once and four times daily, respectively. Both treatment groups had significantly lower prevalence and severity olfactory and gustatory dysfunction. Prevalence was lower for the drug vs. saline group, without statistical significance.
Nov 2023, QJM: An Int. J. Medicine, https://academic.oup.com/qjmed/advance-article/doi/10.1093/qjmed/hcad262/7439598, https://c19p.org/jingnaclnacl
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/tanninacl
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/lin8nacl
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/delicnaclnacl
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/kimura2nacl
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/bonnnaclnacl
7. 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/chalagerisanacl
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