Ivomec ( 1% ivermectin and dogs)?

Could I use the new low-tox antifreeze by prestone (99.95% propylene glycol - .05% Sodium Nitrite) to dilute Ivomec (1% Ivermectin) to a level safe for dogs (for heartworm prevention) or should I continue to special order PG off the internet. No one close to me sells it.