Join Date: May 2009
Location: Mid Northern TN
Comfortis is the drug spinosad, which when combined with heartworm protection, is sold as Trifexis. I love it, think it works great, especially for dogs or cats who are allergic to fleas. That said, I go with the Trifexis because it's just a little more and then it covers fleas, heartworms, and most intestinal parasites all in one go. It does cause an upset stomach in the occasional dog, especially if not given with food though.
Most drugs that cause sedation also make it more difficult for animals to control their temperature properly and balance well enough to avoid falling while in a vehicle. Since you'll be traveling in the heat, I think it would be pretty risky. IF the animal must be sedated for safety, it might be different, but generally I avoid sedating animals for travel if there are other alternatives.