Anyone that isn't a doctor would be a fool to give you advice on the dosage. You should go to your doctor for this information.
This post is only as an example and should be used by no one as any recommendation.
But for the purpose of an exercise only...
Look at the FLCCC I-Mask protocol if you want general information related to what you are asking.
https://covid19criticalcare.com/covid-19-protocols/i-mask-plus-protocol/For an example, they recommend .4mg/kg of body weight if you have been exposed. If you are a 250 pound person, you weigh close to 113.4 KG.
113.4*.4 = 45.4 mg/kg.
According to this paste, if, IF, I have done the math correctly,
https://www.durvet.com/wp-content/uploads/2017/12/ivermectin-paste_box_6.08g_0221_e.pdfOne notch contains enough ivermectin for a 250 lb horse at a dosage of 91mcg per pound. So:
91mcg*250 = 22,750 mcg or 22.7mg.
IF i have done my math correctly then 2 notches equal roughly 45.5 mg. Which is pretty dang close to the 45.4 recommend.
But please don't listen to me or any of this information. This was only to show as an example based on my non-medical educated understanding of what the FLCCC recommends and what the particular ivermectin paste i chose as an example would be.