Join Date: Feb 2016
Location: Central Michigan
Submit Photo: 23
Photo Submissions 24 Times in 24 Posts
I have heard that ivermectin, the active ingredient in the Heartguard product, is no longer 100% effective against heartworms. Sentinel contains different ingredients which I don't remember how to spell. It helps with control of fleas by preventing the eggs from developing into larvae.
So yes, I've heard this but am unfamiliar with reactions in Havanese.
Zigfield Lola Bleu