I couldn't find any info on ivermectin is only effective for 18 days,
but I did find this post that was interesting. in particular, it (pt 2)
says that it takes 3 months for microfilaria to grow to a larval stage
inside a dog, and if the dog is dosed with ivermectin at any time, the
larvae will never develp into adult worms and will die. wondering if
anyone can comment on the accuracy of this.

<http://terriermandotcom.blogspot.ca/2008/05/billion-dollar-heartworm-scam.html>

Selina

[Posted in FML 7387]