Quote:
Originally Posted by Ellie May  Heartworm drugs are actually a cure, not a prevention. Sentinel would kill any larvae at a certain stage and then the drug leaves the system. It is done about once every 30 days because of the stages that the larvae goes thorough. |
From what I understand, the new ones are both, a cure and a preventative. From what the OP posted earlier, it is not out of their system in 4 days.