In an acute process like COVID-19 in its advanced stages or in sepsis it may make sense to block both H1R and H2R to avoid organ damage. To the extent that the negative feedback mechanism that regulates the production of histamine (H2R-H3R) is exceeded or does not work properly, that same histamine and also the rest of the products of the mast cells and the rest of the immune cells will cause massive damage (keep in mind that histamine receptors are not only in immune cells but in all tissues).
Critical role of endogenous histamine in promoting end-organ tissue injury in sepsis.
Background Histamine assumes an important role as a major mediator in various pathologic disorders associated with inflammation and immune reactions. However, the involvement of histamine in the pathological conditions and symptoms of sepsis remains entirely unknown. In this study, we establish...
icm-experimental.springeropen.com
Another more interesting option would be to look for an immunomodulation with histamine that would allow to restore this negative feedback mechanism.
Histamine receptor agonist alleviates severe cardiorenal damages by eliciting anti-inflammatory programming.
Histamine has been known to play important roles in inflammation, and its inhibition has been expected to ameliorate the pathological statement of heart failure and chronic kidney disease. In this paper, we found that histamine is elevated in the plasma of a preclinical mouse model with severe...
www.pnas.org
And another option compatible with the previous one would be to use IV vitamin C.
Hydrocortisone, Ascorbic Acid and Thiamine (HAT Therapy) for the Treatment of Sepsis. Focus on Ascorbic Acid.
Sepsis is a devastating disease that carries an enormous toll in terms of human suffering and lives lost. Over 100 novel pharmacologic agents that targeted specific molecules or pathways have failed to improve the outcome of sepsis. Preliminary data suggests that the combination of...
www.mdpi.com
Intravenous infusion of ascorbic acid decreases serum histamine concentrations in patients with allergic and non-allergic diseases.
Histamine plays an important role in the development of symptoms in allergic, infectious, neoplastic and other diseases. Empirical findings have suggested beneficial effects of ascorbic acid supplementation in those diseases, and these effects are assumed to be related to a possible decrease in...
link.springer.com
This is another preprint on the topic of COVID-19 and histamine, although they forget that one of the characteristics of famotidine and other H2R antagonists is that they are very powerful radical scavengers.
COVID-19: Famotidine, Histamine, Mast Cells, and Mechanisms
SARS-CoV-2 infection is required for COVID-19, but many signs and symptoms of COVID-19 differ from common acute viral diseases. Currently, there are no pre- or post-exposure prophylactic COVID-19 medical countermeasures. Clinical data suggest that famotidine may mitigate COVID-19 disease,...
www.researchsquare.com
Cimetidine and other H2 receptor antagonists as powerful hydroxyl radical scavengers.
Hydroxyl radical scavengers are able to compete with deoxyribose for the hydroxyl radicals generated in a reaction mixture. We found that the H2 recep…
www.sciencedirect.com
H2‐receptor antagonists are scavengers of oxygen radicals.
onlinelibrary.wiley.com