Dog Health Questions? Ask a Dog Vet for Answers ASAP
Hi Customer, Thank you for your question about your dog.
I would advise against this. The dose of ivermectin to treat a 60 pound dog would be less than a milligram a day , by mouth is best. A .08% drench should be .8 milligrams in one ml (one cc), so one cc (about 15 drops) would be the daily dose. Applying this small amount topically probably would not be effective against demodectic mange, and it should not be given orally.
There is a further complication that some dogs have the "MDR" gene which makes them 10 times more sensitive to ivermectin, and a dose as high as a milligram could put them in a coma, or worse.
The MDR gene is uncommon, but if your dog has it, this would be dangerous.
When I treat demodex, I use the cattle wormer Ivomec, and give tiny amounts by mouth daily for 3 to 6 months. I warn the owners about the MDR gene, and recommend testing for it. If they want to try the Ivomec without testing, I have them sign a waiver that says they understand the risk.
What would be the recommended dose using cattle wormer Ivomec? Is there any problem using Ivomec after he has been on Promeris?
Ivomec is one milligram (10,000 micrograms) per one tenth of a cc (ml). A 60 pound dog (that does not have the MDR gene) would need about 8000 micrograms as a dose, daily, for a month after a negative skin scraping for mites. This would be 0.8 of a cc (ml). You will need a one cc syringe to measure accurately.
You have to do skin scrapings to tell when it is time to stop; you can't tell if the mites are gone just by looking at the dog.
Again, if he has the MDR gene, this is a dangerous dose. Most dogs with the MDR gene are collies and Australian shepards, but it has been seen in many breeds and in mixed breed dogs.
It should be safe to do this with Promeris. You will not need to put him on heartworm preventative while he is on the Ivomec. Another thing to be sure of is his heartworm status; the Ivomec could be dangerous if he has heartworms.
Hope this helps, Rebecca
I just was reading about Promeris ( we don't have fleas here where I live so I have not used it) and after writing you I went to close the window and this caught my eye:Promeris is just now labeled for treatment of Demodex. Were you using it for fleas, or to treat the Demodex?
It might be safer to use the Promeris, since using the Ivomec is an "offlabel" use of this cattle wormer. Again, if you were my client and going to use Ivomec to treat the Demodex, I would have you sign a waiver stating that you understand the possible serious side effects, and understand that using Ivomec is off label. Now that Promeris is labelled for Demodex, this is what I would use first.