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pokey1984 t1_j7w5akn wrote

Reply to comment by rdizzy1223 in According to a study on 12,211 patients, aspirin is just as effective at preventing blood clots as low molecular weight heparin, but it costs less and is easier to administer by giuliomagnifico

Because "more aspirin" doesn't thin the blood any more than a low dose.

After 81 mgs, you don't see any increase in the amount it thins the blood and higher doses over extended periods can be hard on the stomach and kidneys.

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TinFoilHeadphones t1_j7w6nom wrote

81mg for what body weight?

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Pro-Karyote t1_j7w865m wrote

For daily prophylactic use, it’s 81mg for all body weights (though the actual definition of low-dose aspirin is anything less than 100mg per day - 81mg is traditionally the dose for historical reasons).

Current Aspirin Guidelines

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tjeulink t1_j7wl80m wrote

Historical reasons on medicine dosages? Now im interested haha

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Pro-Karyote t1_j7wp06j wrote

It has to do with a unit of measurement we don’t currently use for dosing medications, called a grain. The full dose of aspirin was 5 grains, which is about 325mg. The low dose was a quarter of the full dose, so 1.25 grains (which is roughly 81mg). That was the dose that was on formulary, and since it falls within the low-dose range and it was the dose available, it stuck.

Brief overview of aspiring dosing history

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TinFoilHeadphones t1_j7xgrnp wrote

Oh, that explains. I thought he said such a specific number as 81mg because of some calculations. I couldn't understand why such a weird number.

(I don't live in the USA, so measurements here are different)

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pokey1984 t1_j7w9zb8 wrote

It's pretty universal. I'm sure some adjustments meed to be made for people who weigh like 600lbs, but for pretty much everyone else 81mgs is sufficient.

My mom is on Aspirin, Elliquis, and Warfarin for her heart problems because simply adding more aspirin or increasing either of the other drugs doesn't do enough. Most drugs reach a maximum effective level and after that more of the drug doesn't have any more effect. That's why people with serious problems will be on so many different medications instead of just taking a huge dose of one drug.

And in most cases, body weight is irrelevant. Certain drugs, yes, body weight matters. That's true of anesthetics and a few other types of drugs. But for most of them weight doesn't matter.

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Lunaranalog t1_j7z6df9 wrote

Warfarin and Eliquis? Her cardio trying to make her bleed to death? That’s some serious dual therapy. I’ve never seen that. She must be a case study if that’s true.

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pokey1984 t1_j81b0qv wrote

Not a case study, just bad heart/blood pressure issues. She's already had one stroke and two stents. She has A-fib and damage to one of her ventricles from an "undiagnosed" heart attack. (It wasn't diagnosed as a heart attack and she didn't have any symptoms of a heart attack, but she has damage that's evidence of a heart attack.) So they're trying to keep her heart from over working itself, trying to keep her arteries from clogging any worse, while trying to keep the stents from throwing any more clots while also not overwhelming her kidneys and liver.

So she's on a low dose of three blood thinners for the time being to try and protect her heart and lungs and eyes from further damage without destroying her kidneys.

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