Ivermectin, a potent dewormer that is frequently prescribed in veterinary practice, treats a variety of parasites in dogs, including internal parasites as well as ear and hair mites. Additionally, this drug guards against heartworm infections brought on by Dirofilaria immitis. Ivermectin specifically kills heartworm larvae (microfilaria) in afflicted dogs’ blood.
Ivermectin, despite being generally regarded as safe, can be toxic to dogs, leading to neurological abnormalities like depression, drooling, anorexia, vomiting, pupil dilation and blindness, inability to stand or exert control over their own movements, disorientation, tremors, and seizures, as well as coma.
The most frequent causes of ivermectin toxicosis in dogs are either unintentional overdoses (such as consuming the feces of large animals like horses who have recently undergone ivermectin deworming) or genetic mutations that make them more vulnerable to the drug’s effects.
The p-glycoprotein protein is produced as a result of a genetic mutation in the MDR1 gene, also known as the ABCB1 gene. P-glycoprotein, which is found all across the body, is essential for removing medicines from cells. Additionally, the blood-brain barrier contains the p-glycoprotein, which serves to prevent some drugs like ivermectin from entering the central nervous system. Ivermectin can easily move from the bloodstream into the central nervous system in dogs who have mutant forms of p-glycoprotein, leading to neurological problems.
Researchers soon discovered that a range of other herding-breed dogs also contained this genetic mutation after it was initially discovered in collies in the 1980s. Long-haired whippets, Australian, English, and German shepherds, Shetland and Old English sheepdogs, and border collies are a few examples of such breeds.
It is crucial to understand that dogs with a mutation in the MDR1/ABCB1 gene are often only harmful to larger doses of ivermectin, such as those used to treat mange or ear mites. All ivermectin-based heartworm preventatives created in the US and recognized by the FDA as safe for use in all dogs, including those with the mutation, In other words, a dog should not be denied heartworm prevention simply because they have a genetic mutation in the MDR1/ABCB1 gene.
A recent study by the American Heartworm Society found that heartworm affects tens of thousands of dogs every year and that an increasing number of canines are testing positive for the disease. More specifically, more than 77,500 of the over 7 million heartworm tests conducted in 2013 were positive. Nearly 119,000 of 9.2 million heartworm tests were positive by 2016, representing an increase in positive tests of 15.28%. Therefore, heartworm prevention is recommended for all pets.
To prevent dogs from ingesting equine deworming products, horse owners should be careful with how they store and discard them.
If a dog starts to exhibit any neurologic clinical symptoms, get them to the vet right once. Ivermectin toxicosis in dogs can be effectively recognized and treated, resulting in full recovery.
A dog’s physical appearance should not be used to confirm or disprove the presence of the MDR1/ABCB1 mutation, especially in mixed-breed dogs. Genetic testing is the only technique to determine if a dog has the mutation or not. For details on genetic testing and how to interpret the results, consult your veterinarian.
Can I use horse wormer on my dog?
Please be advised that you shouldn’t deworm your horses in the presence of dogs or cats. This week, a client called to inform us that their tiny Yorkie dog had spent the weekend receiving treatment at the small animal emergency facility because to a hazardous exposure to Quest (moxidectin). Before they could stop her, the dog sucked up a tiny bit of the gel, and within minutes she was clearly very sick. Due to their quick response, she has healed and is now at home after they took her to the emergency facility.
Both the active ingredients in Quest, moxectin, and many brand-name equine dewormers, ivermectin, can be extremely hazardous to dogs and cats. These chemicals are present in the horse products at quantities that are harmful to small animals. Toxicity for small animals just requires a very small amount.
Drooling, dilated pupils, lack of coordination, and trembling are symptoms of toxic exposure, which proceed to seizures, coma, and eventually death if untreated.
Please keep your pets inside the house while deworming your horses, and make sure the used syringes are properly disposed of. Keep your dog away from the pastures and paddocks for a few days if they enjoy eating horse excrement. Even though it happens very infrequently, it is possible for dogs to consume toxic doses by consuming newly dewormed horses’ excrement.
Can dogs with heartworms be given ivermectin?
Ivermectin is most frequently prescribed to dogs and cats to prevent heartworm disease. Additionally, a number of internal and external parasites were treated with drugs that were “off label” or “extra-label.” Ivermectin, for instance, can be used to treat intestinal parasites including hookworms and roundworms in dogs as well as capillaries, mites, and scabies. Ivermectin can be used to treat cat scabies and ear mites in cats.
In veterinary medicine, many medications are frequently used for off-label uses. In these situations, pay close attention to your veterinarian’s instructions and warnings.
How is ivermectin given?
Other deworming drugs may be taken in addition to ivermectin. Ivermectin is offered as tablets, chewable tablets, a topical liquid (for treating ear mites), and an injection that will be given to your pet by your veterinarian.
You can administer it with or without food. Give the medication with food or a little treat to see if that helps if your pet vomits or acts sick after receiving it on an empty stomach. In case the vomiting persists, call your veterinarian.
The procedure for applying topical ivermectin to your pet’s ears will be explained by your veterinarian.
The effects of this drug should be felt within one to two hours, but they might not be immediately apparent. As a result, laboratory tests may be necessary to assess this medication’s efficacy.
What if I miss giving my pet the medication (or my shipment is late)?
As soon as you remember, administer the missing dose; after that, wait the period of time between doses that your veterinarian has advised before administering the subsequent dose. Don’t administer additional dosages or two doses at once to your dog.
If you are taking ivermectin to prevent heartworms and it has been more than 8 weeks since your last dose, speak with your veterinarian for advice.
Are there any potential side effects?
Ivermectin is normally well tolerated but when used in large doses, such as for mite infestations, it can have substantial neurological adverse effects.
Certain breeds, like collies, are only moderately sensitive to ivermectin dosages and may have negative effects at lesser levels.
Some dogs may get a reaction resembling shock from ivermectin. Contact your veterinarian if this occurs.
Contact your veterinarian if you have any side effects, including as nausea, vomiting, diarrhea, dilated pupils, unsteadiness when walking, or a confused temperament.
The effects of this quick-acting medicine should wear off after 24 hours, though they may last longer in animals with liver or renal illness.
Are there any risk factors for this medication?
Ivermectin shouldn’t be administered to puppies under 6 weeks of age or to animals lacking a recent negative heartworm test.
Ivermectin sensitivity varies among dog breeds; examples include collies, sheepdogs, and collie- or sheepdog-cross breeds. This is frequently caused by a particular genetic mutation (MDR1) that reduces their tolerance for large doses of ivermectin. These dog breeds can safely receive heartworm preventive doses.
Are there any drug interactions I should be aware of?
There are some drugs that intensify ivermectin’s effects in a pet’s brain (e.g., ketoconazole, itraconazole, cyclosporine, erythromycin, amlodipine besylate, and nifedipine). Spinosad, a popular flea preventive medication, should not be supplied when high dosages of ivermectin are used to treat mite infestations. Combining spinosad with the minimal doses of ivermectin seen in heartworm preventives is safe.
Tell your vet about any medications your pet is receiving, including vitamins, supplements, and herbal treatments.
Is there any monitoring that needs to be done with this medication?
Before administering the medication, screening may be carried out on breeds of dogs who may be sensitive to ivermectin. A pet’s genetic mutation that causes negative reactions to ivermectin can be detected by DNA testing.
How do I store ivermectin?
Ivermectin-based products should be kept at room temperature, away from heat sources, in a dry, cold environment. The effectiveness of the medication may be lowered by heat or moisture exposure.
What should I do in case of emergency?
Call your veterinarian’s office right away if you think your pet may have taken too much medication or is having an unfavorable reaction to it. Follow their instructions for contacting an emergency facility if they are not readily available.
Do heartworms die after deworming?
In the Southern United States and wherever else where mosquitoes are found, canine heartworm disease is quite prevalent. Here are the heartworm facts so you can safeguard your pet in that regard.
What exactly are heartworms?
Heartworms are worms that develop and dwell inside the dog’s heart. They impair the heart’s capacity to circulate blood throughout the body. They can also harm other organs including the heart and cause heart failure and lung illness. Heartworms are ultimately fatal if neglected!
How do dogs get heartworm disease?
Mosquitoes transmit heartworms from dogs to dogs. For instance, a mosquito can spread the disease when it bites a dog that already has heartworms. As a result, the heartworms are spread to another dog when that mosquito bites it. In fact, dogs can contract heartworm disease from a mosquito bite alone!
How do I know if my dog has heartworms?
The only way to find out is to get a heartworm test from your veterinarian. In order to obtain heartworm preventative, your dog actually needs to have a negative heartworm test. So, request an annual one from your veterinarian.
My dog looks healthy. Does that mean that he doesn’t have heartworms?
In dogs, heartworm disease can be challenging to diagnose. Dogs with heartworms, for example, may not exhibit any physical symptoms until they have had them for a long time. Physical signs may include having trouble breathing while moving around or playing, coughing up blood, or even having an extremely big abdomen.
If I buy dewormer medicine at the store and give it to my dog, will that prevent or kill heartworms?
No. Roundworms and hookworms in the intestines are eliminated by deworming medications. But they fail to eradicate heartworms. Dewormers do not work on heartworms because they reside in blood vessels, not the intestines. The only medication that can stop heartworms from spreading is heartworm preventive. Numerous anti-heartworm medications help eliminate intestinal parasites.
How can I prevent my dog from getting heartworms?
Utilizing a heartworm prevention medication is the only way to avoid contracting heartworms. The most typical is a chewable treat that you give your dog on a regular basis. Through a veterinarian, you can buy heartworm prevention medication. Additionally, with a prescription from your doctor, you may buy it online from pet retailers like Chewy or Petco. The medication has a monthly cost of $10 to $30. Some products also protect against ticks and fleas. To keep your dog safe, be sure to keep them on preventive throughout the year.
Can heartworms be passed to my other dogs?
Not exactly. Heartworms cannot be passed from one dog to another since they are carried and spread by mosquitoes. Heartworms can only be spread by mosquitoes and are not contagious.
My dog is always indoors. Does that mean that he is safe from getting heartworms?
A mosquito can get inside your home and bite your dog even if they never go outdoors. Consequently, even if your dog is always indoors, there is no assurance of protection!
What dosage of ivermectin should I give my dog to treat heartworm?
Ivermectin dosage is based on the parasite and dog’s body weight. The dosage, for instance, is 0.0015-0.003 milligrams per pound (0.003 to 0.006 milligrams/kilogram) given once per month to prevent heartworms. It is 0.15 milligram per pound (0.3 milligram per kilogram) and must be repeated after 14 days for skin parasites. The single dose for internal worms is 0.1 milligram per pound (0.2 milligram per kilogram).
Ivermectin should be given to your dog as soon as you remember if you mistakenly neglect to do so. The dog’s heartworm protection is already damaged if you are more than two weeks late, so see your veterinarian first.
Never give your dog an extra dose to make up for a missed one. This medicine can overdose if used in excess. Mydriasis (dilated pupils), ataxia (lack of coordination), vocalization, blindness, dementia, disorientation, coma, and possibly death are symptoms of ivermectin toxicity in dogs, a potentially fatal condition.
