“This all became an issue, because I wanted a prescription for heartguard, to get remy started as soon as I could. The rescue says to start it may 5, a month after his injections. My vet on the other hand, won’t prescribe, because he believes Remy is “off treatment schedule” and said he can have a toxic reaction to the heartguard. – is this true???”
Yes, from what I understand this is true. You do not give heartworm meds to a heartworm positive dog.
That is why the annual heartworm test is required before veterinarians will prescribe heartworm preventives. If the dog is heartworm positive it will aggravate the condition if they take the pesticides.
