I started Huey on Program, but ran out (was ordering online), and when I went to the vet to pick some up, they didn't carry it so I changed to comfortis. I was also giving heartworm pills, so finally changed to trifexis. I have had him on that for almost 2 years. He never had trouble with any of them. He is 7.5 lbs now, but I originally started the meds when he was less than 4 lbs. |