Back in April I did some research on mixing your own HW preventative and started a discussion here on DK. I wanted to post an update. I did indeed order Ivermectin and propylene glycol along with a small dark glass bottle for mixing and the right size syringe for measuring the doses. We are on month 3 of making our own HW prevention doses. Because the propylene glycol is slightly sweet I don't need to hide the dose in anything special; I just squirt the dose over everyone's dinner and they gobble it down. The dosage guide I ultimately used also prevents tapes, hooks and other worms. We have had no side effects whatsoever.
If I had to complain about anything (which I can't) is that I had to buy 10 syringes when I only need one for measuring. :)