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Micro-clots: a big piece of the Long Covid puzzle?


Over the last year, a number of studies have shown that Covid causes microclots of the blood, which are not detected by standard imaging or blood tests.

Microclots are a problem because they make blood sticky, preventing proper blood flow. This means that blood cells (along with vital oxygen and nutrients) are not able to reach all parts of the body, especially in capillaries. This can have huge effects on any part of the body, including heart, lungs, brain and many others. (Dr. Asad Kahn, a respiratory practitioner that is also a long hauler, purports to have a photograph of microclotted blood. I do not have a way to verify the authenticity of the photo, but wow -- it's really something.)

When the body is functioning normally, clots are routinely cleared from your system. But for many with Long Covid, this process is impaired.

A study published in December 2021 shows how these microclots might be treated. Researchers found that anticoagulant/anti-platelet therapy dissolved microclots for people after Covid infection.

There’s been a lot of buzz in the science world about this. But there are some caveats.

My own experience with Plavix

I've been a long hauler since August 2020, and I haven't yet fully recovered. I'm particularly intrigued in this new study because, about a month ago, I started taking some new prescription meds, including one of the antiplatelet drugs (Plavix) that they used in the study. This may explain why some (but not all) of my symptoms improved noticeably.

Back in 2020 I'd read a scientific paper that suggested Covid causes microclotting. When I mentioned it to a couple doctors at the time, they dismissed it as unlikely and unprovable. One of them even said that microclots "don't exist." (He also said I just needed to exercise more.)

The treatment

The study showed that 1 month of a triple anticoagulant/anti-platelet drug cocktail helped patients:

  • Plavix (clopidogrel) 75mg, once daily
  • Aspirin 75mg, once daily
  • Eliquis (apixaban) 5 mg, twice per day
  • Pantoprazole 40 mg/day was also prescribed for gastric protection

Why 3 anticoagulants? Because each one operates via a different mechanism. The study's leader, Dr. Resia Pretorius, says it appears that a multi-pronged approach is needed -- otherwise the microclot problem can return.

Once fully resolved, it looks like microclots don't come back -- unless the patient is reinfected with Covid.

The study's authors are quick to point-out:

  • This was a relatively small study of about 70 people.
  • This study was not a randomized, controlled trial.
  • Taking more than one anticoagulant can actually be deadly.

The biggest risk of taking more than one anticoagulant/antiplatelet drug is internal bleeding, which is not always easy to identify -- especially if you're already dealing with an array of odd symptoms from Long Covid.

Pantoprazole can help reduce the chance of GI bleeding. However there are still serious risks from taking multiple anticoagulants/antiplatelets, including a potentially fatal brain hemorrhage.

Mitigating risk

The study's authors suggest two measures to mitigate risk somewhat:

  • Use tests to confirm if the patient actually has microclots.
  • Use tests to confirm if the therapy is actually working.
The problem is that these tests are not widely available to consumers today. And even with the tests, you may still have internal bleeding.

It remains to be seen whether such testing could be made more available, or if other established tests might also provide important biomarkers.

My perspective

I'm not a doctor or a scientist. I'm simply a long hauler that reads a lot -- and a data nerd.

More studies are desperately needed to confirm these findings. But there could be big potential here, especially because these medications are well-established and widely available.

I don't know if this would magically fix everything for all long haulers, but it might be a big piece of the puzzle for many of us.

Long Covid is an umbrella term that includes a handful of different syndromes, and long haulers likely have some combination of them. Each person's experience is a little different, so microclots may not be present in everyone. Researchers are identifying other contributors, including autoimmunity, mitochondrial dysfunction, organ damage, viral reactivation and gut dysbiosis.

The proposed therapy comes with real risks. More studies will help us know if there are ways to mitigate this risk -- perhaps with new tests, different drugs or other interventions.

To state the obvious: you should not attempt to obtain medications illegally. You should not try this therapy without medical supervision. And this therapy is not intended to be taken long-term.

It looks like there's a third-party company called RTHM that may be positioning itself to offer treatments. They're accepting applicants, possibly to participate in studies. (I have no experience or association with them whatsoever, though I may decide to enroll in their program to learn more.)

Here's the full scientific paper: Combined triple treatment of fibrin amyloid microclots and platelet pathology in individuals with Long COVID/PASC can resolve their persistent symptoms.

There's also a very interesting interview with Dr. Resia Pretorius, who led the study.

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