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Keep your dog safe from heartworms! Learn their causes, recognize key symptoms, and get expert prevention strategies to protect your pet from these deadly parasites.
Updated on July 16th, 2026
Learn how to remove flea and ticks. Petco has flea and tick removal services for dogs and cats. Get fleas and ticks removed at your neighborhood Petco.
Updated on July 28th, 2026
Learn how to improve your dog's life with nutritional probiotics. Help your dog regardless of age or size & manage inflammation, gastrointestinal health & arthritis.
Updated on June 19th, 2026
Learn about the benefits of fish oil for dogs. Order online from Petco and save with Autoship or Curbside Pickup.
Updated on June 19th, 2026
Vet authorized diets are typically needed only when a pet has specific health issues, but learning about how they're different from "normal" foods can help you be a more well-rounded pet parent.
Updated on June 19th, 2026
Tri-Heart is generic Heartgard and is just as effective. I am not sure why your vet won't prescribe it for you. You cannot buy any heartworm prevention over the counter so you will need a prescription. I suggest you bring your dog to one of the VETCO vaccine clinics at your local Petco stores (see schedule below). Bring proof of his last negative heartworm test and they can give you a prescription for the Tri-Heart. There is no charge for the exam. Just the cost of the medication. Hope this helps! ( https://www.vetcoclinics.com/services-and-clinics/clinic-locations-and-schedules/?zip=77469 ) ( https://www.petco.com/shop/SearchDisplay?categoryId=&storeId=10151&catalogId=10051&langId=-1&sType=SimpleSearch&resultCatEntryType=2&showResultsPage=true&searchSource=Q&pageView=&beginIndex=0&pageSize=48&fromPageValue=search&searchTerm=triheart )
Updated on September 24th, 2025
Hello. This is fine to use. I would not recommend giving both of these on the same day. Give one on the first of the month & the second on the 15th so there are no drug interactions. Thanks for using Petco Pet Education Center, formerly Petcoach.
Updated on September 24th, 2025
We don't sell prescription drugs here since we are only a consulting forum. However, if you want to do comparison prices for drugs then the best resource is https://www.goodrx.com OR calling the pharmacy of your choosing directly. I wish you all the best and hope that you can find an affordable price for your pets medication. Take care!
Updated on September 24th, 2025
Both doxycycline and prednisone can cause vomiting and diarrhea. I am not sure of the dose that your dog is on but maybe your vet could adjust the dose so he has less gastrointestinal problems. Feeding the medication with a meal can sometimes help with the gastrointestinal side effects so make sure to give with food. Your vet could also prescribe an anti-vomiting medication, probiotic, and GI protectant which may help, too. At this point, If he is just going to vomit the medication than it doesn't make sense to give it. You should wait and see if your vet can prescribe additional medications to help with the vomiting and diarrhea. If the vomiting and diarrhea has stopped, you could try to give one medication at a time with food and see how he does.
Updated on September 24th, 2025
Medications get approved after going through many tests. If the test for a certain medication preparation (e.g. Ivermectin comes in various oral pastes, injection solutions, chews, spot ons, etc) is done for a particular animal species only, then it will only be licensed for that. So Heart Guard chews would not be licensed for horses or cattle , as it was not tested for them to be protected against heart worms, but since it was tested on dogs to be effective against heart worm, it would be licensed for dogs.. Ivomec injection solution was tested against certain parasites in cattle and therefore would only be licensed for cattle, unless the company manufacturing the injection solution would test it on dogs against heart worm also, It's complicated. Some preparations of the same medication may be detrimental for one species , but not for another, yet the basic medication may be the same. I hope this helps with your query. Please let me know if you have any other questions or concerns and I would be more than happy to help you further. Please take the time to mark this question as helpful or not as it helps us to improve on the quality of our answers to other pet owners. Thank you kindly!
Updated on September 24th, 2025