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COVID-19: Famotidine, Histamine, Mast Cells, and Mechanisms
Robert W Malone1, Philip Tisdall2, Philip Fremont-Smith3
1RW Malone MD LLC, Madison, VA.
Research Square
|July 24, 2020
Summary
Famotidine may help treat COVID-19 by targeting histamine H2 receptors. This research explores how famotidine may work by affecting mast cells and histamine release in COVID-19 patients.
Area of Science:
- Infectious Diseases
- Pharmacology
- Immunology
Background:
- COVID-19, caused by SARS-CoV-2, presents with varied symptoms distinct from typical viral illnesses.
- No current medical countermeasures exist for preventing or treating COVID-19 before or after exposure.
- Clinical observations suggest famotidine might alleviate COVID-19 symptoms, yet its mechanism and optimal dosage remain unclear.
Purpose of the Study:
- To investigate the potential therapeutic mechanisms of famotidine in mitigating COVID-19.
- To elucidate the role of histamine pathways and mast cell activation in COVID-19 pathogenesis.
- To provide a rationale for famotidine's efficacy and guide future clinical development.
Main Methods:
- Exploration of potential antiviral activities of famotidine.
- Investigation of host-mediated effects, including immune responses.
- Analysis of famotidine's interaction with histamine receptors, specifically H2.
- Examination of mast cell activation and histamine release in the context of COVID-19.
Main Results:
- Proposed that famotidine's primary action in COVID-19 involves specific histamine H2 receptor activity.
- Hypothesized that COVID-19 progression is linked to abnormal mast cell activation and subsequent histamine release.
- Identified potential pathways for famotidine's therapeutic effect beyond direct antiviral action.
Conclusions:
- Famotidine's efficacy in COVID-19 may be attributed to its histamine H2 receptor antagonism.
- Dysfunctional mast cell activation and histamine release are implicated in the development of clinical COVID-19.
- Further research into famotidine's role in modulating histamine pathways could lead to novel COVID-19 treatments.
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