Iota-carrageenan was adopted
by organizations in 1 country.
Jul 3 |
Iota-carrageenan for COVID-19: real-time meta analysis of 1 study | |
| Significantly lower risk is seen for cases. Meta analysis using the most serious outcome reported shows 80% [22‑95%] lower risk. Currently there is very limited data, with only one study to date. 1 RCT with 480 patients has not.. | ||
Feb 11 |
et al., International Journal of Biological Macromolecules, doi:10.1016/j.ijbiomac.2025.140920 | Green antiseptic for hand hygiene with high activity against SARS-CoV-2: Iota-carrageenan, quercetin, and Melaleuca alternifolia essential oil based nanoemulsion |
| In Vitro study showing that a nanoemulsion combining quercetin, iota-carrageenan, and Melaleuca alternifolia (tea tree) essential oil inhibited SARS-CoV-2 replication by 100% in epithelial cells, with no cytotoxicity observed. Authors dev.. | ||
Feb 6 |
et al., PLOS ONE, doi:10.1371/journal.pone.0316700 | Over-the-counter carrageenan-based sprays may interfere with PCR testing of nasopharyngeal swabs to detect SARS-CoV-2 |
| In Vitro study showing that carrageenan may interfere with PCR testing for SARS-CoV-2 on nasopharyngeal swabs, potentially leading to false negative results. Seegene STARlet was most affected, frequently returning invalid results, while q.. | ||
Apr 9 2024 |
et al., Microbiology Research, doi:10.3390/microbiolres15020035 | Polysaccharides and Lectins: A Natural Complementary Approach against the SARS-CoV-2 Pandemic |
| Review of polysaccharides and lectins as a complementary approach against SARS-CoV-2. Authors discuss the antiviral activity of various polysaccharides like carrageenans, heparin, chondroitin sulfates, hyaluronans, fucoidans, and alginate.. | ||
Mar 28 2024 |
et al., International Journal of Nanomedicine, doi:10.2147/IJN.S448005 | Lipid Nanoparticle-Based Inhibitors for SARS-CoV-2 Host Cell Infection |
| In Vitro study showing that lactoferrin, camostat mesylate, and carrageenan inhibit SARS-CoV-2 pseudovirus infection in airway epithelial Calu-3 cells. All show dose-dependent inhibition. The study focuses on novel LNP formulations and t.. | ||
Jul 31 2023 |
et al., Stresses, doi:10.3390/stresses3030039 | Algae Polysaccharides (Carrageenan and Alginate)—A Treasure-Trove of Antiviral Compounds: An In Silico Approach to Identify Potential Candidates for Inhibition of S1-RBD Spike Protein of SARS-CoV-2 |
| In Silico study showing the potential antiviral activity of algal polysaccharides alginate and carrageenan against SARS-CoV-2. Molecular docking analyses predict that alginate and carrageenan can bind to and inhibit the viral S1-RBD spike.. | ||
Jul 5 2023 |
et al., Nutraceuticals, doi:10.3390/nutraceuticals3030025 | Iota-Carrageenan Inhibits Replication of the SARS-CoV-2 Variants of Concern Omicron BA.1, BA.2 and BA.5 |
| In Vitro study showing that iota-carrageenan inhibits SARS-CoV-2 replication for omicron variants BA.1, BA.2 and BA.5. Iota-carrageenan was more effective than kappa- and lambda-carrageenan. | ||
Feb 27 2023 |
et al., Pharmacological Reports, doi:10.1007/s43440-023-00463-7 | Nasal sprays for treating COVID-19: a scientific note |
| Review of nasal sprays for treatment of COVID-19. Authors note that the nasal epithelium is typically the primary site of SARS-CoV-2 infection, and there may be significant advantages for treatments via the nasal route. | ||
Nov 22 2022 |
, H., Journal of Bioinformatics and Genomics, doi:10.18454/jbg.2022.18.2.001 | The potential of carrageenan for the drug discovery of COVID-19 via molecular docking with angiotensin-converting enzyme 2 (ACE2) and the main protease (Mpro) of SARS-CoV-2 |
| In SIlico study identifying significant binding affinity for ACE2 and Mpro with kappa-, lambda-, and iota-carrageenan. | ||
Nov 18 2022 |
et al., NCT04590365 | Efficacy of Carrageenan Nasal and Throat Spray for COVID-19 Prophylaxis - A Double Blind Randomised Placebo-controlled Trial |
| 480 participant iota-carrageenan prophylaxis RCT with results not reported over 2 years after completion. | ||
Sep 30 2022 |
et al., Proceedings of the National Academy of Sciences, doi:10.1073/pnas.2209514119 | SARS-CoV-2 requires acidic pH to infect cells |
| Real-time 3D single-virion tracking study showing that SARS-CoV-2 infection requires an acidic pH. Authors find the mean pH of the airway-facing surface of the nasal cavity to be 6.6, compatible with fusion. These results suggest a benefi.. | ||
Feb 28 2022 |
et al., Journal of Hospital Infection, doi:10.1016/j.jhin.2021.10.019 | Virucidal activity of nasal sprays against severe acute respiratory syndrome coronavirus-2 |
| In Vitro study of seven nasal sprays and two oral sprays showing 3.4x lower viral load (log viral load 5.98->5.45) with a nasal spray containing carragelose (1.2 mg/mL), kappa-carrageenan (0.4 mg/mL), and sodium chlorite. The most effecti.. | ||
Jan 28 2022 |
et al., Frontiers in Drug Delivery, doi:10.3389/fddev.2023.1164671 (date from preprint) | On a model-based approach to improve intranasal spray targeting for respiratory viral infections |
| Computational fluid dynamics study of nasal spray administration in 2 subjects showing 100x improvement in nasopharyngeal drug delivery using a new spray placement protocol. The study also found the optimal droplet size range for nasophar.. | ||
Dec 15 2021 |
et al., Biochemistry and Biophysics Reports, doi:10.1016/j.bbrep.2021.101187 | Iota-carrageenan extracted from red algae is a potent inhibitor of SARS-CoV-2 infection in reconstituted human airway epithelia |
| In Vitro study showing iota-carrageenan inhibits SARS-CoV-2 in reconstituted human airway epithelia. Authors note that the absence of toxicity or any functional or structural impairment of the bronchial mucociliary epithelium indicates th.. | ||
Dec 8 2021 |
et al., International Journal of Molecular Sciences, doi:10.3390/ijms222413202 | Iota-Carrageenan Inhibits Replication of SARS-CoV-2 and the Respective Variants of Concern Alpha, Beta, Gamma and Delta |
| In Vitro study of iota-, lambda-, and kappa-carrageenan sulfated polysaccharides extracted from red seaweed on SARS-CoV-2 Wuhan type and variants Alpha, Beta, Gamma and Delta, showing that all three carrageenan types had antiviral activit.. | ||
Oct 31 2021 |
, A., Clinical Epidemiology and Global Health, doi:10.1016/j.cegh.2021.100826 | The antiviral activity of iota-, kappa-, and lambda-carrageenan against COVID-19: A critical review |
| Review of the antiviral activity of iota-, kappa-, and lambda-carrageenan against SARS-CoV-2. Carrageenan, a polymer derived from marine algae, has shown potent in vitro antiviral activity against SARS-CoV-2, with iota-carrageenan having .. | ||
Sep 7 2021 |
et al., International Journal of General Medicine, doi:10.2147/IJGM.S325861 | The Saliva of Probands Sucking an Iota-Carrageenan Containing Lozenge Inhibits Viral Binding and Replication of the Most Predominant Common Cold Viruses and SARS-CoV-2 |
| Prospective study of 31 subjects analyzing iota-carrageenan concentration in saliva after using an iota-carrageenan containing lozenge, showing sufficient concentration to neutralize common respiratory viruses including SARS-CoV-2. For SA.. | ||
Aug 30 2021 |
et al., NCT04681001 | Clinical Trial to Evaluate the Efficacy of an Iota-Carrageenan Nasal Spray to Reduce Symptoms Caused by SARS-CoV-2 and Other Respiratory Viruses in Healthcare Workers Managing COVID-19 Patients |
| 300 participant iota-carrageenan prophylaxis RCT with results not reported over 3 years after completion. Authors indicate that there were no SARS-CoV-2 infections in either group. The trial record also suggests there was no placebo group.. | ||
Jul 26 2021 |
et al., Marine Drugs, doi:10.3390/md19080418 | Griffithsin and Carrageenan Combination Results in Antiviral Synergy against SARS-CoV-1 and 2 in a Pseudoviral Model |
| In Vitro and In Silico analysis showing SARS-CoV-2 antiviral activity of carageenan, and synergistic activity from the combination of carrageenan and griffithsin. | ||
Jun 16 2021 |
et al., Frontiers in Medical Technology, doi:10.3389/fmedt.2021.687681 | Low Acyl Gellan as an Excipient to Improve the Sprayability and Mucoadhesion of Iota Carrageenan in a Nasal Spray to Prevent Infection With SARS-CoV-2 |
| Formulation of a carrageenan nasal spray using gellan as an excipient to improve sprayability and mucoadhesion. Authors report 4x greater coverage versus carrageenan alone. See also [Moakes]. | ||
Jun 14 2021 |
et al., Pharmacology Research and Perspectives, doi:10.1002/prp2.810 | Carrageenan nasal spray may double the rate of recovery from coronavirus and influenza virus infections: Re-analysis of randomized trial data |
| Individual patient data meta analysis of two RCTs showing nasal iota-carrageenan improved recovery rate and shortened the duration of long colds. There was a 71% reduction in the risk of long colds (>20 days). The increase in recovery rat.. | ||
May 31 2021 |
et al., Advanced Materials, doi:10.1002/adma.202008304 | Formulation of a Composite Nasal Spray Enabling Enhanced Surface Coverage and Prophylaxis of SARS‐COV‐2 |
| Formulation of a mucoadhesive antiviral nasal spray showing efficacy for prophylaxis and against transmission. In Vitro analysis shows prophylaxis with λ-carrageenan demonstrated complete inhibition of SARS-CoV-2 over 48h. A combination o.. | ||
Apr 28 2021 |
et al., American Journal of Physiology: Lung Cellular and Molecular Physiology, doi:10.1152/ajplung.00552.2020 | Carrageenan-containing over-the-counter nasal and oral sprays inhibit SARS-CoV-2 infection of airway epithelial cultures |
| In Vitro study showing that carrageenan-containing nose spray and mouth spray inhibit SARS-CoV-2 in human airway epithelial cultures. | ||
Apr 27 2021 |
et al., bioRxiv, doi:10.1101/2021.04.27.441512 | Iota-carrageenan prevents the replication of SARS-CoV-2 on an in vitro respiratory epithelium model |
| In Vitro Calu-3 (human respiratory epithelial cell line) study showing that iota-carrageenan inhibits SARS-CoV-2. | ||
Apr 15 2021 |
et al., International Journal of General Medicine, doi:10.2147/IJGM.S328486 (date from preprint) | Efficacy of a nasal spray containing Iota-Carrageenan in the prophylaxis of COVID-19 in hospital personnel dedicated to patients care with COVID-19 disease A pragmatic multicenter, randomized, double-blind, placebo-controlled trial (CARR-COV-02) |
| 80% fewer symptomatic cases (p=0.03). Prophylaxis RCT with 394 healthcare workers, 196 treated with iota-carrageenan, showing significantly lower symptomatic cases with treatment. There were no deaths or hospitalizations. There was a significant number of PCR- symptomatic cas.. | ||
Feb 17 2021 |
et al., PLoS ONE, doi:10.1371/journal.pone.0237480 | Iota-carrageenan neutralizes SARS-CoV-2 and inhibits viral replication in vitro |
| In Vitro study showing that SARS-CoV-2 is inhibited by iota-carrageenan in a dose dependent manner and to the same extent as other respiratory viruses for which a clinical benefit has been proven. Authors note that clinical data and post .. | ||
Jan 11 2021 |
et al., American Journal of Therapeutics, doi:10.1097/MJT.0000000000001433 | Intensive Treatment With Ivermectin and Iota-Carrageenan as Pre-exposure Prophylaxis for COVID-19 in Health Care Workers From Tucuman, Argentina |
| 95% fewer moderate/severe cases (p=0.002) and 84% fewer cases (p=0.004). Prophylaxis RCT for ivermectin and iota-carrageenan in Argentina, 117 healthcare workers treated with ivermectin and iota-carrageenan, and 117 controls, showing significantly lower cases with treatment. There were no moderate/severe cases.. | ||
Dec 29 2020 |
et al., Bioresource Technology Reports, doi:10.1016/j.biteb.2020.100623 | Antiviral activity of sulfated polysaccharides from marine algae and its application in combating COVID-19: Mini review |
| Review of the antiviral activity of marine sulfated polysaccharides including carrageenan, and the mechanisms of action for inhibiting different stages of viral infection. | ||
Nov 17 2020 |
et al., Journal of Biomedical Research and Clinical Investigation, doi:10.31546/2633-8653.1007 | Study of the Efficacy and Safety of Topical Ivermectin + Iota-Carrageenan in the Prophylaxis against COVID-19 in Health Personnel |
| 100% fewer cases (p<0.0001). Prophylaxis study using ivermectin and iota-carrageenan showing 0 of 788 cases from treated healthcare workers, compared to 237 of 407 control. See [doyourownresearch.substack.com] for discussion of issues with this trial. | ||
Oct 19 2020 |
et al., NCT04425850 | Usefulness of Topic Ivermectin and Carrageenan to Prevent Contagion of Covid 19 (IVERCAR) |
| 96% fewer cases (p<0.0001). Prophylaxis study using ivermectin and carrageenan showing 0 of 131 cases from treated healthcare workers, compared to 11 of 98 control. The effect is likely to be primarily due to ivermectin - the author has later reported that carrageen.. | ||
Aug 24 2020 |
et al., Food & Function, doi:10.1039/D0FO02017F | Inhibitory activities of marine sulfated polysaccharides against SARS-CoV-2 |
| In Vitro study showing significant antiviral activity of marine sulfated polysaccharides iota-carrageenan, sea cucumber sulfated polysaccharide, and fucoidan. | ||
Aug 21 2020 |
et al., PLoS ONE, doi:10.1371/journal.pone.0259943 (date from preprint) | Iota-carrageenan and xylitol inhibit SARS-CoV-2 in Vero cell culture |
| In Vitro study showing that iota-carrageenan in concentrations as low as 6 µg/mL (easily achievable with existing nasal sprays) inhibits SARS-CoV-2 in Vero cell cultures. | ||
Jun 29 2020 |
et al., Research Square, doi:10.21203/rs.3.rs-37994/v1 | Repositioning Therapeutics for COVID-19: Virtual Screening of the Potent Synthetic and Natural Compounds as SARS-CoV-2 3CLpro Inhibitors |
| In Silico study identifying kappa-carrageenan and other compounds as potential candidates for SARS-CoV-2 inhibition. | ||
Feb 28 2017 |
et al., International Journal of General Medicine, doi:10.2147/IJGM.S120665 | Amylmetacresol/2,4-dichlorobenzyl alcohol, hexylresorcinol, or carrageenan lozenges as active treatments for sore throat |
| Pre-COVID In Vitro study showing iota-carrageenan lozenges effective against respiratory viruses HRV1a, HRV8, Coxsackievirus A10, influenza A H1N1n, and hCoV OC43. | ||
Nov 12 2014 |
et al., Multidisciplinary Respiratory Medicine, doi:10.1186/2049-6958-9-57 | Carrageenan nasal spray in virus confirmed common cold: individual patient data analysis of two randomized controlled trials |
| Analysis of 2 RCTs concluding that carrageenan nasal spray reduced duration of virus-confirmed common colds, increased viral clearance, and reduced relapses. | ||
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