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Comment by margalabargala | Hacker News Reader

Edit: I accidentally used the stock concentration in my original calculation, updated to the effective dose found.

The average volume of a human is around 62 liters.

The effective concentration for the highest EC50 is 6.71mM. The lowest EC50 is 1.31.

Aspirin DL-lysine as a molecular weight of 326.34.

Therefore, to reach the concentrations used in the study, the average person would have to consume somewhere between 26 and 135g of asprin (from the two molarities above). Way above the maximum safe daily dose, which is 4 grams.

Using the absolute best case scenario- 1.31mM- and an effective volume of 12 liters, that's still 5.1g. Which is /just/ under the max safe dose. At 6.71mM, that's 26g.

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Drugs don't spread out evenly through the whole body. For this class of drug, it's bloodstream concentration that matters.

The complex field of pharmacokinetics relates the bloodstream concentration to the ingested amount over time. The simple version uses a "volume of distribution" which, for salicylate, is 11.9 liters for a standard male. [https://sepia.unil.ch/pharmacology/index.php?id=83].

So to achieve the 1 - 7 milimolar concentrations they used would require 3.8 - 27.2 grams of aspirin.

What's the half-life of aspirin in the bloodstream? Probably less than a day, which would significantly increase the dose required to maintain those concentrations.

It seems like this might merit further research as a treatment for severe cases, but it's far too dangerous to be a prophylactic for healthy people.

(And that's all assuming these results on other coronaviruses apply to the new coronavirus that causes COVID-19.)

This kills the kidneys

These calculations aren't helpful at all.

Drugs don't evenly distribute in the body. Some drugs get bound to specific proteins, so the observed concentration is much lower (i.e. higher volume of distribution). Others get concentrated in specific organs once they equilibrate across the body.

Sure, but unless we have some reason to think that this will have some reason to concentrate in the lungs in particular its a quick sanity check. Maybe it does concentrate in the lungs and this'll be a great medicine but a priori we don't have any reason to expect that and this is a reason not to get our hopes up.

At those concentrations I suspect there is a whole lot of substances that kill the virus (along with the host).

Option B: Or we could raise our blood alcohol level at 60%-70% by volume, apparently that kills the virus :)

To be more precise: 50 millimolar was the stock concentration, not the concentration used in the experiments. The effective concentrations were between 1 and 7 millimolar.

> The results indicate an effective concentration 50 (EC50) of 1.31 mM for HCoV-229E resulting in a selectivity index (SI: CC50/IC50) of 15.6 as well as an EC50 of 3.69 mM for MERS-CoV, leading to an SI of 15.9, similar to that of HCoV-229E (Figures 2D and 2E). The EC50 for HCoV-229E-infected PBMCs at 24 h was 6.71 mM resulting in an SI of 5.7 (Figure 2F).

And if tlb is right that the volume of distribution is under 12 liters, the dose required in the best case would be approximately the maximum dose of aspirin (4 grams). In the worst case, far more.

That would be 12 325mg aspirins. Which is too much, but almost in the ballpark.

Thanks for catching that. I've updated the math in my comment.

Exactly what I came to the comments for... dimensional analysis, done right - you the real mvp! Thanks.

Reminds me of this:

https://xkcd.com/1217/

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