Forum Discussion
BCSnob
Oct 22, 2015Explorer
rockhillmanor wrote:It would be nice if you would read the information about the MDR1 mutation provided by those doing the research.NO!! I really doubt the dosing of an avermectin at the preventive dose has anything to do with his seizures.
The OP stated they are using Sentinel that is milbemycin Oxime based.
IMHO when there is ongoing research on collies having a mutation related to the use of milbemycin oxime that can cause seizures. It would seem real prudent to stop using that heart worm med that has it as an ingredient.
Ivermectin (antiparasitic agent)- While the dose of ivermectin used to prevent heartworm infection is SAFE in dogs with the mutation (6 micrograms per kilogram), higher doses, such as those used for treating mange (300-600 micrograms per kilogram) will cause neurological toxicity in dogs that are homozygous for the MDR1 mutation (MDR1 mutant/mutant) and can cause toxicity in dogs that are heterozygous for the mutation (MDR1 mutant/normal).
Selamectin, milbemycin, and moxidectin (antaparasitic agents)- Similar to ivermectin, these drugs are safe in dogs with the mutation if used for heartworm prevention at the manufacturer’s recommended dose. Higher doses (generally 10-20 times higher than the heartworm prevention dose) have been documented to cause neurological toxicity in dogs with the MDR1 mutation.
source: WA State Veterinary Clinical Pharmacology Lab: MDR1 Problem Drugs
This information very clearly states that the doses used for heartworm preventative are SAFE. If you have them, please provide links to research studies (not website posted hearsay) that offer contradictory data indicating that these drugs (used at the heartworm preventative doses) trigger neurological toxicity caused symptoms in dogs with the MDR1 mutation.
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