Have you looked into whether cinchona is really an acceptable substitute for chloroquine?
I’m concerned for two reasons. First, the studies I saw were on chloroquine, and I don’t know if quinine is the same as chloroquine for this purpose. They have slightly different antimalarial activity—some chloroquine-resistant malaria strains are still vulnerable to quinine—and I can’t find any information about whether their antiviral activity is the same. They’re two pretty different molecules and I don’t think it’s fair to say that anything that works for one will also work for the other. Even if they do work, I don’t know how to convert doses. It looks like the usual quinine dose for malaria is about three times the usual chloroquine dose, but I have no idea how that translates to antiviral properties.
Second, I don’t know how much actual quinine is in cinchona. Quinine is a pretty dangerous substance, so the fact that the FDA doesn’t care if people sell cinchona makes me think there isn’t much in it. This paper suggests 6 mg quinine per gram of bark, though it’s using literal bark and not the purified bark product they sell in supplement stores. At that rate, using this as an example cinchona preparation and naively assuming that quinine dose = chloroquine dose, the dose corresponding to the Chinese studies would be 160 cinchona pills, twice a day, for ten days - a level at which some other alkaloid in cinchona bark could potentially kill you.
Also, reverse-quarantining doesn’t just benefit you, it also benefits the people who you might infect if you get the disease, and the person whose hospital bed you might be taking if you get the disease. I don’t know what these numbers are but they should probably figure into your calculation.
This is a relevant study I found on quinine’s antiviral activity (albeit on a different virus):
A previous study reported that the
antimalarial drug chloroquine, a drug that shares a similar chemical
property with quinine (both are alkaline in nature), inhibits pH-dependent
stages of Flavivirus replication (Randolph et al., 1990). This is a
likely inhibitory mechanism of quinine in our experimental model.
Also, reverse-quarantining doesn’t just benefit you, it also benefits the people who you might infect if you get the disease, and the person whose hospital bed you might be taking if you get the disease. I don’t know what these numbers are but they should probably figure into your calculation.
I wanted to start with something very simple to avoid decision paralysis, but you’re right that there are flow-through / flatten-the-curve benefits. I’ve added a note clarifying that while this consideration matters, I haven’t counted it.
Have you looked into whether cinchona is really an acceptable substitute for chloroquine?
Nope! The epistemic status there is something like “rumor from a pretty sensible and curious friend.” Definitely not a substitute for any other measure, and highly speculative. Edited to clarify (and link to your comment).
“Tonic water contains no more than 83 mg of quinine per liter,” according to the FDA. I haven’t found any tonic water brands that say how close they come to that threshold, but 3 2L bottles of tonic water per day could keep you well-hydrated *and* protected.
From what I can google, typical dosage of quinine for malaria would be at least 500mg every 8 hours. If you drink 6 liters of tonic water every 8 hours you’ll have more to worry about than coronavirus. What I don’t understand is why they haven’t started treating Covid with chloroquine yet—it’s cheap and plentiful and has minimal side effects. Are desperate doctors in overwhelmed ICUs really holding off just because it would be off-label?
Have you looked into whether cinchona is really an acceptable substitute for chloroquine?
I’m concerned for two reasons. First, the studies I saw were on chloroquine, and I don’t know if quinine is the same as chloroquine for this purpose. They have slightly different antimalarial activity—some chloroquine-resistant malaria strains are still vulnerable to quinine—and I can’t find any information about whether their antiviral activity is the same. They’re two pretty different molecules and I don’t think it’s fair to say that anything that works for one will also work for the other. Even if they do work, I don’t know how to convert doses. It looks like the usual quinine dose for malaria is about three times the usual chloroquine dose, but I have no idea how that translates to antiviral properties.
Second, I don’t know how much actual quinine is in cinchona. Quinine is a pretty dangerous substance, so the fact that the FDA doesn’t care if people sell cinchona makes me think there isn’t much in it. This paper suggests 6 mg quinine per gram of bark, though it’s using literal bark and not the purified bark product they sell in supplement stores. At that rate, using this as an example cinchona preparation and naively assuming that quinine dose = chloroquine dose, the dose corresponding to the Chinese studies would be 160 cinchona pills, twice a day, for ten days - a level at which some other alkaloid in cinchona bark could potentially kill you.
Also, reverse-quarantining doesn’t just benefit you, it also benefits the people who you might infect if you get the disease, and the person whose hospital bed you might be taking if you get the disease. I don’t know what these numbers are but they should probably figure into your calculation.
This is a relevant study I found on quinine’s antiviral activity (albeit on a different virus):
I wanted to start with something very simple to avoid decision paralysis, but you’re right that there are flow-through / flatten-the-curve benefits. I’ve added a note clarifying that while this consideration matters, I haven’t counted it.
Nope! The epistemic status there is something like “rumor from a pretty sensible and curious friend.” Definitely not a substitute for any other measure, and highly speculative. Edited to clarify (and link to your comment).
“Tonic water contains no more than 83 mg of quinine per liter,” according to the FDA. I haven’t found any tonic water brands that say how close they come to that threshold, but 3 2L bottles of tonic water per day could keep you well-hydrated *and* protected.
From what I can google, typical dosage of quinine for malaria would be at least 500mg every 8 hours. If you drink 6 liters of tonic water every 8 hours you’ll have more to worry about than coronavirus. What I don’t understand is why they haven’t started treating Covid with chloroquine yet—it’s cheap and plentiful and has minimal side effects. Are desperate doctors in overwhelmed ICUs really holding off just because it would be off-label?