first, the methylated form - selenomethionine - is the safest form i know of. up to 800mcg can be taken daily of that form.

be well

Hello yellpant,

As a rule of thumb I read somewhere here on the forum we can take 100mcg of Selenium per 50mg of Iodine, without exceeding the 800mcg that Trapper mentioned above.
Also, I would suggest to start from a lower dosage not straight away 300mg Iodine.