Some of the medications the Thai government are using for those with Covid are pretty questionable anyway.
Stay home and get well yourself. You could get some Fathalaijone, ฟ้าทะลายโจร, at the pharmacy if you wanted. It's an herb. Very bitter if you taste some of it directly.
In some places it is called "the king of bitters".
King of bitters facts | Health Benefits (healthbenefitstimes.com)