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COVID-19: Famotidine, Histamine, Mast Cells, and Mechanisms
Robert W Malone1,2, Philip Tisdall3, Philip Fremont-Smith4
1RW Malone MD LLC, Madison, VA, United States.
Frontiers in Pharmacology
|April 9, 2021
Summary
Famotidine may alleviate COVID-19 symptoms by targeting histamine H2 receptors, suggesting a role for mast cell activation in disease development. This research supports new drug repurposing strategies for COVID-19 treatment.
Area of Science:
- Virology and Immunology
- Pharmacology
Background:
- Severe acute respiratory syndrome-coronavirus 2 (SARS-CoV-2) infection causes COVID-19, presenting symptoms distinct from typical viral illnesses.
- Existing medical countermeasures for pre- or post-exposure prophylaxis against COVID-19 are not approved.
- Clinical observations suggest famotidine might mitigate COVID-19, but its mechanism and optimal dosage are unclear.
Purpose of the Study:
- To investigate plausible mechanisms of action for famotidine's potential efficacy in COVID-19.
- To explore both antiviral and host-mediated pathways involved in famotidine's activity.
- To hypothesize the role of histamine and mast cell activation in COVID-19 pathogenesis.
Main Methods:
- Investigated multiple hypotheses regarding famotidine's antiviral and host-mediated effects.
- Analyzed the potential involvement of histamine receptor H2 activity.
- Examined the role of mast cell activation and subsequent histamine release in COVID-19.
Main Results:
- Proposed that famotidine's primary mechanism for symptom relief in COVID-19 involves direct histamine H2 receptor activity.
- Hypothesized that dysfunctional mast cell activation and histamine release are implicated in clinical COVID-19 development.
- Identified potential for famotidine-based therapeutic strategies.
Conclusions:
- Famotidine's efficacy in COVID-19 may be linked to its histamine H2 receptor antagonism.
- Dysfunctional mast cell activation appears to be a key factor in COVID-19.
- This research underpins the development of novel, multi-drug COVID-19 treatment strategies using repurposed, accessible medications.
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