First, be sure you need something before you take it. Besides ivermectin, this site has threads about chlorine dioxide and also about hydrogen peroxide being effective. Also, there are other sources of ivermectin ... it's available over the counter for dogs as well. (Heartgard- same name has ivermectin alone, and ivermectin with other medicines).

But if you want to try ... Search on the poison control center. Inevitably there are reports "help: my kid just swallowed a tube of horse medicine" with an answer by the staff. Or you can call the company's contract number with a similar story to see what they say. On this board I haven't seen any reports of ivermectin + other stuff. Yet.