The study they rely on Tang W et al from BMJ uses 1200 mg/day x 3 then 800 mg/day for 2-3 weeks… thats really high… toxicity is in the dosage
The Tang W et al paper from BMJ immdietaly attacks trump in their introduction.
https://www.bmj.com/content/369/bmj.m1849
US president Donald Trump also recently recommended use of hydroxychloroquine. Such a presidential endorsement stimulated an rapid increase in demand for hydroxychloroquine, which obscured the negative aspects of this drug.