What Every Dog Owner Should Know About Ivermectin
Parasites can wreak havoc on dogs, and ivermectin is a go-to defense, but it’s not a one-size-fits-all solution. Some breeds handle it just fine, while others can have dangerous reactions. Understanding how it works and what to watch out for can help you make the best choices for your pup. So, let’s get into the details.
What Ivermectin Does For Dogs
Ivermectin is a versatile dewormer that targets intestinal, lung, and external parasites while also helping prevent heartworm in dogs. It comes in several forms, including injectables, oral solutions, pastes, topicals, pour-ons, chewables, and pills. While effective, some breeds are highly sensitive to it, making proper dosing essential.
Common Uses
Veterinarians frequently prescribe ivermectin as a heartworm preventative, typically in low monthly doses that stop immature larvae from maturing into adult heartworms. Because heartworm disease is expensive and difficult to treat, prevention is far safer and more affordable. Ivermectin is also used to treat sarcoptic and demodectic mange, which are skin conditions caused by microscopic mites.
How It Prevents Parasites
Ivermectin binds to glutamate-gated chloride channels in parasites, disrupting their nervous system and causing paralysis. This makes it highly effective against heartworm larvae and prevents them from blocking arteries and causing heart failure. However, ivermectin at standard preventive doses does not kill adult heartworms; higher doses may reduce adults but aren’t a full cure.
How Long Ivermectin Stays In A Dog’s System
The time ivermectin stays in a dog’s system depends on factors like dosage, breed, and metabolism. Its effects typically last around 48 hours, though small traces can linger for weeks. Some breeds process it more slowly, increasing the risk of side effects with prolonged exposure.
When To Avoid Using Ivermectin
Pregnant and nursing dogs can safely receive ivermectin at standard heartworm preventive doses, though higher treatment doses require caution due to potential metabolic differences. Consult a vet for specific cases. Those with neurological disorders should also avoid it, as it can worsen symptoms.
Safe Dosages For Different Breeds
The proper ivermectin dosage depends on a dog’s size, breed, and overall health. Larger breeds generally tolerate standard doses well. On the other hand, Collies, Australian Shepherds, Shetland Sheepdogs, Longhaired Whippets, Old English Sheepdogs, and related breeds may not adequately process ivermectin due to the MDR1 gene mutation.
Signs Of Ivermectin Toxicity
Early warning signs include dilated pupils, drooling, vomiting, and loss of coordination. As toxicity worsens, symptoms can progress to tremors, seizures, respiratory distress, and even coma. In severe cases, untreated poisoning can cause permanent neurological damage or be fatal.
What To Do If Overdosed
Symptoms of overdose can take a few hours to appear, but they progress rapidly. If you suspect an overdose, call a veterinarian or a poison control hotline immediately. Activated charcoal can sometimes slow absorption, but professional treatment is usually necessary. Veterinary care may include IV fluids, oxygen therapy, and medications to control seizures.
Mixing Ivermectin With Other Medications
Certain medicines can intensify ivermectin’s effects, leading to a higher risk of toxicity. Medications like the antifungal ketoconazole, antibiotic erythromycin, and flea/tick preventative spinosad can interfere with ivermectin’s metabolism, increasing its potency and toxicity risk. Because of this, tell your veterinarian about all medications your dog is taking.
Safer Alternatives For Sensitive Dogs
Some heartworm preventatives use active ingredients, such as milbemycin oxime or selamectin, which are safer for ivermectin-sensitive breeds. Topical treatments for fleas, ticks, and mites provide another option. In areas with high parasite exposure, vets may suggest a combination of approaches to ensure complete protection without putting the dog at risk.
