Ivermectin for Dogs

Ivermectin, a fairly new medication, is an anti-parasitic drug chiefly used for treating and managing heartworm infection in dogs. However, Ivermectin is often prescribed as an ‘extra-label’ drug for the treatment of demodectic and sarcoptic mange, ear mites, and parasitic infestations affecting dogs’ visceral or external organs.

Ivermectin at a Glance

Can You Administer Ivermectin Safely to Your Dog?

If and when your vet prescribes Ivermectin as an off-label medication for your pet, follow the recommendations very carefully. You can safely administer Ivermectin to your dog to effectively treat parasitic infections provided you follow the vet’s dosage instructions. FDA has allowed the drug’s use (entailing moderate dosage) for dealing with heartworm disease and ear mite management in dogs.

Nevertheless, the dosage increases substantially (by nearly 50 times) when it comes to other extra-label applications of Ivermectin, thereby enhancing the risk of toxicity. Vets exclusively recommend this drug for use as a preventative therapy rather than administering it to dogs already infected with heartworms. Additionally Ivermectin should not be given to dogs bearing the MDR1 gene as the drug brings about permanent neurotoxicity or irreversible CNS damage.

Action Mechanism of Ivermectin

Ivermectin disables and damages the central nervous system of heartworm larvae from the pupal stage through to the imaginal stage. Consequently, the routine functioning of the heartworm’s nervous system is adversely affected leading to the paralysis and death of the parasite. The modus-operandi of Ivermectin remains the same when the drug is administered for the treatment and control of other parasitic mites.

Appropriate Ivermectin Dosage for Dogs

Ivermectin dosage is not standardized but varies based on the dog’s breed, the animal’s weight, and the diagnosed parasitic infection. Before the vet prescribes the drug, he’ll or she’ll carry out a few tests to establish whether the dog has preexisting heartworm disease. If the diagnostic assays confirm heartworms’ presence, the veterinarian first prescribes suitable medications for doing away with the parasitic heartworms.

Once the vet is convinced that the heartworms have been eliminated, she may prescribe Ivermectin for checking the parasite’s further breeding. The dog is usually kept under therapeutic supervision for at least 8 hours following the administration of the medication. The vet may prescribe Ivermectin together with other Anthelmintic or de-worming drugs for the first few weeks.

Though you can offer the medication without food, administering the medication alongside food prevents or arrests the urge to throw up. Apart from chewable tablets, Ivermectin is also available as a topical liquid or an injectable liquid for treating ear mites. It normally takes around 1-2 hours for the medication to start acting on the parasite’s nervous system but the effects are not palpable.  

Likely Side Effects

The most common side-effects associated with Ivermectin occur by and large when you offer a higher-than-normal dose. Following are some of the adverse effects that are most likely to happen with a larger dosage of Ivermectin: -

• Dilated and enlarged pupil
• Acute dehydration
• Muscle tremor
• Lethargy
• Anorexia (loss of appetite)
• Vomiting
• Drooling

Drug Contraindications

Always tell the vet about your dog’s medical history, the animal’s weight and age, and the medicines you’re offering if any. Ivermectin may interact with a certain class of drugs such as immunosuppressants, antifungals, antibiotics and sedatives. Your vet will not prescribe the medication if your dog is not an adult because of the animal’s undeveloped blood-brain barrier.

Disclaimer: The above content is based on multiple research articles referred to online. Global Dog Breeds intends to share information, but it's strictly advised to consult a veterinarian and seek advice before using any medications described. We believe each condition and dog is unique, and only after careful evaluation from a qualified professional should you be offering any medications to your pet.