Heparin seems to reduce progression of COVID-19 in hospitalized people with moderate symptoms but not for the critically ill. Study author states that more research required to find the therapeutic “sweet spot”.

Medical Mythbusting Commentary for August 5, 2021

Source:
Canadian-led studies suggest blood thinner can help moderately sick COVID-19 patients

Reference:
Therapeutic Anticoagulation with Heparin in Critically Ill Patients with Covid-19
Therapeutic Anticoagulation with Heparin in Noncritically Ill Patients with Covid-19

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