Dec 23 |
Antihistamine H1RAs reduce COVID-19 risk: real-time meta analysis of 16 studies | |
| Significantly lower risk is seen for mortality, recovery, cases, and viral clearance. 9 studies from 8 independent teams in 5 countries show significant benefit. Meta analysis using the most serious outcome reported shows 37% [21R.. | ||
Dec 13 |
et al., Microorganisms, doi:10.3390/microorganisms12122589 | COVID-19 in Relation to Chronic Antihistamine Prescription |
| Retrospective 140,681 patients in Spain showing lower COVID-19 infection, hospitalization, and mortality with chronic antihistamine treatment, with a greater protective effect for patients taking 2-7 chronic treatments. Results are provid.. | ||
Nov 26 |
et al., BMC Infectious Diseases, doi:10.1186/s12879-024-10211-8 | Mitigating the risks of post-acute sequelae of SARS-CoV-2 infection (PASC) with intranasal chlorpheniramine: perspectives from the ACCROS studies |
| 90% lower PASC (p=0.001). Prospective study of 259 COVID-19 outpatients from the ACROSS-I and ACROSS-III RCTs showing significantly lower long COVID with intranasal chlorpheniramine (iCPM) compared to placebo. 72% of placebo patients experienced at least one PASC .. | ||
Oct 31 |
et al., MDPI AG, doi:10.20944/preprints202410.2532.v1 | Azelastine Nasal Spray in Non-Hospitalised Subjects with Mild COVID-19 Infection: A Randomized Placebo-Controlled, Parallel-Group, Multicentric, Phase II Clinical Trial |
| 13% improved recovery (p=0.42) and 6% improved viral clearance (p<0.0001). RCT 294 low-risk subjects with mild COVID-19 showing significantly greater reduction in viral load with azelastine 0.1% nasal spray vs. placebo. There was no COVID-19 related hospitalization in either group. The reduction in viral load wa.. | ||
Jul 2 |
et al., mBio, doi:10.1128/mbio.01088-24 | The histamine receptor H1 acts as an alternative receptor for SARS-CoV-2 |
| In Vitro and mouse study showing that antihistamine drugs targeting the histamine receptor H1 (HRH1) inhibit SARS-CoV-2 infection. Authors find that HRH1 acts as an alternative receptor for SARS-CoV-2 by directly binding to the N-terminal.. | ||
Oct 29 2023 |
et al., International Journal of Molecular Sciences, doi:10.3390/ijms242115718 | Sigma Receptor Ligands Prevent COVID Mortality In Vivo: Implications for Future Therapeutics |
| Mouse study showing the combination of lactoferrin and diphenhydramine resulted in slower weight loss, improved survival, and faster weight recovery in SARS-CoV-2 infected animals compared to controls. The study authors propose the.. | ||
Aug 29 2023 |
et al., bioRxiv, doi:10.1101/2023.08.28.554806 | Chlorpheniramine Maleate Displays Multiple Modes of Antiviral Action Against SARS-CoV-2: A Mechanistic Study |
| In Vitro study showing that chlorpheniramine maleate (CPM) inhibits SARS-CoV-2 infection by affecting viral adsorption, replication, and having a direct virucidal effect in Vero E6 cells. Molecular docking analysis revealed that CPM inter.. | ||
Aug 4 2023 |
et al., Pharmaceuticals, doi:10.3390/ph16081107 | Medications Modulating the Acid Sphingomyelinase/Ceramide System and 28-Day Mortality among Patients with SARS-CoV-2: An Observational Study |
| Retrospective 72,105 COVID+ hospitalized patients in France, showing no significant difference in mortality with antihistamine H1RAs desloratadine and hydroxyzine. | ||
Jul 17 2023 |
et al., Frontiers in Cardiovascular Medicine, doi:10.3389/fcvm.2023.1202696 | Antihistamines improve cardiovascular manifestations and other symptoms of long-COVID attributed to mast cell activation |
| 29% lower PASC (p=0.1). Retrospective 14 patients with long-COVID symptoms attributed to mast cell activation treated with H1 and H2 antihistamines compared to 13 control patients, showing significant improvements in several symptoms in the treatment group compa.. | ||
Dec 31 2022 |
et al., Medical Research Archives, doi:10.18103/mra.v10i3.2752 | Intranasal Chlorpheniramine Maleate for the treatment of COVID-19: Translational and Clinical Evidence |
| 87% lower hospitalization (p=0.08). Small RCT showing significantly improved recovery with intranasal chlorpheniramine maleate. Authors also perform an In Vitro study showing efficacy with a highly differentiated three-dimensional model of normal, human-derived tracheal/bro.. | ||
Dec 6 2022 |
et al., Scientific Reports, doi:10.1038/s41598-022-25399-5 | Desloratadine, an FDA-approved cationic amphiphilic drug, inhibits SARS-CoV-2 infection in cell culture and primary human nasal epithelial cells by blocking viral entry |
| In Vitro study showing that desloratadine inhibits SARS-CoV-2 infection in Vero E6 cells, Calu-3 cells, and primary human nasal epithelial cells (HNECs) by blocking viral entry through the endosomal pathway. Authors screened 8 FDA-approve.. | ||
Oct 18 2022 |
et al., Research Square, doi:10.21203/rs.3.rs-2167465/v1 | Chlorpheniramine Intranasal Spray to Accelerate COVID-19 Clinical Recovery in an Outpatient Setting: The ACCROS Trials |
| 54% faster recovery (p<0.0001). RCT and retrospective study of chlorpheniramine nasal spray for COVID-19. The retrospective study included 660 outpatients showing fewer days with general COVID-19 symptoms, cough, anosmia, and ageusia compared to standard of care alone. .. | ||
Oct 18 2022 |
et al., Research Square, doi:10.21203/rs.3.rs-2167465/v1 | Chlorpheniramine Intranasal Spray to Accelerate COVID-19 Clinical Recovery in an Outpatient Setting: The ACCROS Trials |
| 61% improved recovery (p=0.0002) and 74% lower PASC (p=0.001). RCT and retrospective study of chlorpheniramine nasal spray for COVID-19. The RCT included 101 outpatients showing significantly faster recovery with treatment. The retrospective study results are listed separately [Valerio-Pascua]. Long .. | ||
Aug 16 2022 |
et al., Virology Journal, doi:10.1186/s12985-023-02195-9 (date from preprint) | Real-world evidence with a retrospective cohort of 15,968 COVID-19 hospitalized patients suggests 21 new effective treatments |
| 40% lower mortality (p=0.003). Retrospective 15,968 COVID-19 hospitalized patients in Spain, showing lower mortality with antihistamine H1RAs, without statistical significance. Since only hospitalized patients are included, results do not reflect different probabilitie.. | ||
Jun 29 2022 |
et al., Journal of General Internal Medicine, doi:10.1007/s11606-022-07701-3 | Medications Associated with Lower Mortality in a SARS-CoV-2 Positive Cohort of 26,508 Veterans |
| 43% lower mortality (p<0.0001). Retrospective 26,508 consecutive COVID+ veterans in the USA, showing lower mortality with multiple treatments including antihistamines. Treatment was defined as drugs administered ≥50% of the time within 2 weeks post-COVID+, and may be a .. | ||
Jan 8 2022 |
et al., Pharmaceuticals, doi:10.3390/ph15010078 | A Case-Control of Patients with COVID-19 to Explore the Association of Previous Hospitalisation Use of Medication on the Mortality of COVID-19 Disease: A Propensity Score Matching Analysis |
| 80% lower mortality (p=0.05). PSM retrospective 3,712 hospitalized patients in Spain, showing lower mortality with existing use of loratadine. | ||
Jan 6 2022 |
, S., Cureus, doi:10.7759/cureus.20980 | Molecular Modeling and Preliminary Clinical Data Suggesting Antiviral Activity for Chlorpheniramine (Chlorphenamine) Against COVID-19 |
| In Silico study suggesting that the over-the-counter antihistamine chlorpheniramine may have antiviral activity against SARS-CoV-2. Using structural database searches and molecular modeling, authors found that chlorpheniramine shares simi.. | ||
Dec 15 2021 |
et al., Journal of Clinical Medicine, doi:10.3390/jcm10245891 | Hydroxyzine Use and Mortality in Patients Hospitalized for COVID-19: A Multicenter Observational Study |
| 46% lower mortality (p=0.02). Retrospective 15,103 hospitalized COVID-19 patients in France showing lower mortality with hydroxyzine use. | ||
Apr 30 2021 |
et al., Chemico-Biological Interactions, doi:10.1016/j.cbi.2021.109420 | Testing of the inhibitory effects of loratadine and desloratadine on SARS-CoV-2 spike pseudotyped virus viropexis |
| In Vitro study showing that histamine H1 antagonists loratadine (LOR) and desloratadine (DES) inhibit SARS-CoV-2 spike pseudovirus entry into ACE2-overexpressing HEK293T cells, with DES showing greater efficacy. Using cell membrane chroma.. | ||
Apr 30 2021 |
et al., Pulmonary Pharmacology & Therapeutics, doi:10.1016/j.pupt.2021.101989 | Antihistamines and azithromycin as a treatment for COVID-19 on primary health care – A retrospective observational study in elderly patients |
| Retrospective 84 elderly nursing home residents in Spain showing no mortality, hospitalization, or ICU admission with early treatment with antihistamines alone or in combination with azithromycin. | ||
Mar 31 2021 |
et al., Signal Transduction and Targeted Therapy, doi:10.1038/s41392-021-00689-y (date from preprint) | Real-world evidence for improved outcomes with histamine antagonists and aspirin in 22,560 COVID-19 patients |
| 25% lower mortality (p=0.4). PSM retrospective TriNetX database analysis of 1,379 severe COVID-19 patients requiring respiratory support, showing lower mortality with H1RAs+H2RAs versus famotidine alone, without statistical significance. | ||
Feb 22 2021 |
et al., BMC Medicine, doi:10.1186/s12916-021-01907-8 | Relation of severe COVID-19 to polypharmacy and prescribing of psychotropic drugs: the REACT-SCOT case-control study |
| 30% higher severe cases (p=0.0004). Retrospective 4,251 severe COVID-19 cases and 36,738 matched controls in Scotland showing increased risk of severe COVID-19 with PPI use and antihistamine H1RA use. Adjusted results are only provided for the patients not in care homes (2,.. | ||
Jan 31 2021 |
et al., Biochemical and Biophysical Research Communications, doi:10.1016/j.bbrc.2020.11.095 | Identification of antiviral antihistamines for COVID-19 repurposing |
| 34% fewer cases (p<0.0001). Retrospective 219,000 patients showing lower risk of COVID-19 with antihistamine H1RA use. In Vitro study showing these drugs exhibit direct antiviral activity against SARS-CoV-2. Molecular docking suggests hydroxyzine and azelastine may .. | ||
Jan 5 2021 |
et al., bioRxiv, doi:10.1101/2021.01.04.424792 | Hydroxyzine inhibits SARS-CoV-2 Spike protein binding to ACE2 in a qualitative in vitro assay |
| In Vitro study showing that hydroxyzine inhibits the binding of SARS-CoV-2 Spike protein receptor-binding domain (RBD) to ACE2 in a qualitative assay. Hydroxyzine inhibited RBD binding to ACE2 in a dose-dependent manner, while labetalol, .. | ||
Dec 10 2020 |
et al., BMJ Open, doi:10.1136/bmjopen-2020-041577 | Influence of prior comorbidities and chronic medications use on the risk of COVID-19 in adults: a population-based cohort study in Tarragona, Spain |
| 53% fewer cases (p=0.05). Retrospective 79,083 adults aged ≥50 years in Spain showing lower with of PCR-confirmed COVID-19 with antihistamine use, close to statistical significance. | ||
Oct 27 2020 |
et al., medRxiv, doi:10.1101/2020.10.23.20154302 | Association between Hydroxyzine Use and Reduced Mortality in Patients Hospitalized for Coronavirus Disease 2019: Results from a multicenter observational study |
| 58% lower mortality (p=0.001). Retrospective 7,345 hospitalized COVID-19 patients in France showing lower mortality with hydroxyzine use, with a significant dose-response relationship. Hydroxyzine was also associated with a faster decrease in inflammatory markers. | ||
Jul 25 2020 |
et al., The Journal of Clinical Hypertension, doi:10.1111/jch.13948 | Use of distinct anti‐hypertensive drugs and risk for COVID‐19 among hypertensive people: A population‐based cohort study in Southern Catalonia, Spain |
| 61% fewer cases (p=0.1). Retrospective 34,936 hypertensive outpatients in Spain showing no significant difference in COVID-19 cases with PPIs and antihistamine H1RAs. | ||
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