The numbers below assume that IVM is metabolized in one day, which may not be accurate. I couldn't find any specific info on metabolism duration in a quick search.
Non-Covid antiparasite dosage is generally one-time at 0.2mg per kg of bodyweight: Ivermectin Dosage Guide + Max Dose, Adjustments - Drugs.com
Seems that the current covid treatment dose ranges from 0.4 to 0.6 mg per kg.
35mg per week for a 100kg human is 0.05 mg/kg bodyweight per day, or 1/4 the normal parasite treatment dose, and 1/8 or less of the acute covid treatment dose.
Alarmist Covidiot articles are generally quiet on what is the toxicity level. Example: Poison Control Centers Are Fielding A Surge Of Ivermectin Overdose Calls : Coronavirus Updates : NPR
Various googlings hint toward LD50 toxicity ranging from 2 to 100 mg/kg of bodyweight, with an average being 25mg/kg or so. Example source: The multitargeted drug ivermectin: from an antiparasitic agent to a repositioned cancer drug - PMC
At 35mg IVM per week, with daily dose of 0.05 mg/kg bodyweight, he's operating at 1/500 of the LD50 dose. For conversation, LD50 for ibuprofen is 636 mg/kg bodyweight...8 Advils per day for a 100kg human yields 1.6 grams of ibuprofen...about 1/400 of the LD50 dose.
Horse paste tubes dosage? https://www.durvet.com/wp-content/up...te_6.08g-1.pdf
6.08 grams of paste per tube
1.87% ivermectin content = 0.114g per tube
Dosage target per tube is qty (1) 1250lb (567kg) animal. Dosage is therefore 114mg per tube / 567kg = 0.201 mg/kg. Appears to be some intent involved here.
Number of tubes required to achieve LD50 for a 100kg human: 22
Horse paste tubes have bodyweight graduations on the plunger, with a plunger stop. For a 100kg human, threat that sucker to 250lb increments and call it an afternoon. Double or triple that if treating Covid.
IVM pills are 3mg increments, so it may be possible to dose more precisely, easier, with the horse paste. Depends on your skill with the plunger dial or scale usage.
I can maybe? see overdose problems for an innumerate person guzzling injectable or sheep drench. But it would take a good amount of willpower to put away 10 or more tubes of greasy paste, costing $4 each or more. I call BS on the NPR article linked above.