rahaeli: Via @nevadawolf.bsky.social: more evidence that histamine antagonists inhibit SARS-CoV-2 infection and replication and some work on determining the potential mechanism journals.asm.org/doi/10.1128/...

Via @nevadawolf.bsky.social: more evidence that histamine antagonists inhibit SARS-CoV-2 infection and replication and some work on determining the potential mechanism journals.asm.org/doi/10.1128/...

The histamine receptor H1 acts as an alternative receptor for SARS-CoV-2 | mBiojournals.asm.org In addition to human angiotensin-converting enzyme 2, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) can utilize alternative cofactors to facilitate viral entry. In this study, we discov...

This makes intuitive sense because I’m not sure why I haven’t contracted Covid, & I do take a shitload of antihistamines.

My immunocomprised ex was the only one in their house not to get covid when it got in their house. They sat in the same room, unmasked, as everyone else. They credited sitting next to the air filter, which surely didn’t hurt but they also have MCAS and take a shit tonne of antihistamines…

I am absolutely convinced the shitton of antihistamines is why I haven't had it yet *knock wood*

Hope they continue protecting you

I'd wish it had worked for me like that with my basic MCAS treatment.

So funny that there seem to be OTC medications that help protect against Covid, but the chloroquine/Ivermectin crowd likely won’t embrace them.

I know, right!?

Huh. I still haven't had it yet (tho I mask everywhere & avoid indoor gatherings of length). Take an antihistamine daily.

Ok, which brand of antihistamine? Would any be good enough? Will add that to my list of preventative measures when next wave hits.

I have MCAS and take loratidine, cetirizine, and famotidine twice daily. For COVID prevention, loratidine or cetirizine + famotidine is probably good enough.

Thanks again for posting about this -- I took cetirizine and famotidine the last time I got Covid, and while I don't *know* that this isn't why it didn't screw me up as badly for as long as the previous infection, there was a distinct difference in how well I recovered.

This correct? 1. famotidine + cetirizine Or 2. famotidine + loratidine

Correct! One H1, one H2

I can’t find any H2s available OTC in Australia, boo. (I know you can’t do anything about that, I’m just venting.)

The paper implicates the H1 receptor primarily so having that covered is probably the most important thing, which all the over the counter hay fever/insect bite stuff will cover.

I genuinely believe my almost identical antihistamine routine (hydroxyzine instead of famotidine or certizine, I switch those up) is why I avoided a positive Covid test during the exposure that got my spouse even though our exposure vector was the same and then I stayed with him in our studio.

I wonder if my daily MCAS regimen is a factor for me too. I know folks who consistently mask in public and still get it due to, sadly, one-way masking not being quite enough sometimes. But I also have to one-way in public a fair amount for medical appts, and I still haven't caught it.

It's nuts, at the time I was nukeing my gut biome on antibiotics, my immune system is such that I'm a high risk for bacterial infections, but I've never tested positive. Been taking shitloads of antihistamines since the mid 2010s and masking since 2017. I think I've been lucky.

I got it in the fall despite a daily dose of 20 mg cetirizine. Lot of luck involved too with these types of things.

Twice daily or once daily?

if you're high risk, or work in a high risk environment, i'd go 2x per day. if not, 1x is probably sufficient. full disclosure - i take this style of combo meds 1x per day, am not high risk, and wfh. i've also only had covid 1x in the very 1st wave in jan 2020. never since.

^^ that, I take them twice daily but that's for MCAS, people at regular risk are probably okay with once a day unless there's someone in the house with it, in which case 2x/day

Do you think it matters if you take one of each 2x/day or two of one in the morning and two of the other in the evening? I'm thinking that in the run up to going to the dentist I'll take one of each twice a day and that way if I forget a dose I'll still have taken one of each.

Is there any evidence that Flonase would also help? (I looked it up because I went "wait..." and apparently it's a corticosteroid not an antihistamine but now I'm curious if you know!)

So, Flonase is one of the nasal sprays that there is some evidence also provides a small layer of protection against catching covid, it's just almost certainly mitigating via a different mechanism than the antihistamines.

synecdochic.dreamwidth.org/800951.html is rah's entry from last year on nasal sprays

Excellent to know!

Fexofenadine? Neither cetirizine nor loratidine does anything for me.

Yep, also a H1! And if you can't tolerate any of the OTC ones, you can see if you can get a cooperative doctor to prescribe promethazine (Phenergan) which is a nausea med but also a H1 antagonist

Amazing how several antihistamines are primarily used to treat an upset stomach, isn't it?

Yuuuuup. Insert meme here

Meclizine is another that comes to mind. Nausea and vertigo. It's treated weirdly by the pharma PTB, too. It takes a script for >=12.5mg for one use, but can be bought OTC at 25mg with slightly different labeling.

Famotidine is a H2 antagonist, and according to this paper the H2 antagonist they tested didn't prevent viral infection. Who knows what other papers may find, and I take famotidine myself for a different condition, but this paper doesn't indicate it prevents COVID infection, unlike H1s.

pubmed.ncbi.nlm.nih.gov/34994318/ pubmed.ncbi.nlm.nih.gov/37496815/ pubmed.ncbi.nlm.nih.gov/32871242/ pubmed.ncbi.nlm.nih.gov/37529714/ pubmed.ncbi.nlm.nih.gov/37327698/ pubmed.ncbi.nlm.nih.gov/37012686/ pubmed.ncbi.nlm.nih.gov/35768681/ pubmed.ncbi.nlm.nih.gov/35144974/

These are very interesting papers about treating COVID symptoms with famotidine, but the original paper you linked to was about about /prevention/ and in that study famotidine didn't help in that way. As I said I take famotidine daily for a different condition so I think it is the bee's knees myself

pubmed.ncbi.nlm.nih.gov/37012686/ pubmed.ncbi.nlm.nih.gov/35283537/ pubmed.ncbi.nlm.nih.gov/35548336/

📌

I take cetirizine, fluticasone ( oh. That’s a steroid), benedryl and azelastine. Every damn day.

This is rah's post that got me to start taking daily antihistamines. synecdochic.dreamwidth.org/805203.html

Captcha Checksynecdochic.dreamwidth.org

Do be aware of potential medication interactions I can and do take newer H1s (Allegra, Claritin, Zyrtec) but not the H2s (like Pepcid), for example (And older H1s like Benadryl do not play well with my personal biology at all)

Also the next wave is here in many countries. Wastewater numbers are high in the places still tracking.

INTERESTING

this is unfortunately good timing on the share. Just found out some never-covid family members have all finally succumbed, despite being cautious, incl daily loratadine (thinking it was one of those chance outdoor spreads at a gas station or similar) sent it over & hoping they recover fully/swiftly

Any idea about barn door/horse? Was just reading your threads and links yesterday morning on the way to go caving. Spent the day huffing and puffing in tight wet cave passage with 7 other people, one of whom just tested + this morning. Just took a fexofenadine and a famotidine because why not? 🤷🏻‍♀️

It can't hurt, and there's even more evidence that taking both types of antihistimines during an active COVID infection can both help reduce the severity/speed up the recovery and reduce your risk of long COVID! (Good luck.)

Welp, per FDA guidelines, we all dodged that cootie this time. I think everyone did the H1/H2 protocol. Unlike some antihistamines, it didn’t make things get weird for me. So, yay. Got a con in <2wks, prolly take ‘em then, too.

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