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Stay away from giving your dog human pain medications which are toxic to pets.
Updated on June 19th, 2026

Discover how to choose the best supplements for your pet’s health, from essential vitamins to joint support and digestion aids. Learn age-specific and seasonal supplement tips for cats and dogs.
Updated on June 19th, 2026
Do you think your dog might have Leptospirosis? Visit Petco to learn about the signs, symptoms, causes and treatments of Leptospirosis in dogs.
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
Learn how to treat your dog’s bacterial infection and discover how to improve your dog’s skin health. Use Petco’s dog skin infection treatment guide!
Updated on June 19th, 2026
The average dosage of SMZ-TMP for dogs is about 13mg per pound given once daily. For a 50 pound dog this would be about 650mg daily. However, if you need to give a medication such as SMZ to your dog it is best to contact your local veterinarian for the correct dosage and usage information as this dosage can vary depending on your dog's personal needs or illness. Antibiotics should only be given under direct veterinary supervision as the antibiotics you have on hand may not be the correct dosage or even type for your dog's current condition. Giving a medication in the wrong dosage or frequency may make the illness worse or cause side effects that are detrimental to your dog.
Updated on September 24th, 2025
The usual dose used is 15mg/kg but you could go as high as 30mg/kg; so a 26# dog would need between 177mg to 354mg twice a day. I do think the dose is high so please call your vet and ask. Personally I would use 1/2 of a 480mg tablet twice a day. The person who filled the prescription may have made an error. The drug is very safe so I would not be worried about it's safety. Remember, any drug can cause side effects but I use this drug A LOT and very rarely see any side effects and if I do, they are usually mild. ( https://www.petplace.com/article/drug-library/drug-library/library/trimethoprimsulfadiazine-tribrissen-for-dogs-and-cats/ )
Updated on September 24th, 2025
Hi, thanks for using PetCoach! Unfortunately you didn't provide your dogs weight so we can not give you doses. I recommend calling your Vet when they re-open. In the US it is not legal to prescribe medications with out a label and the medications not reconstituted (made in to a liquid from the powder form). Are you in the US? Also in the US we do not prescribe Acetominophen ( https://www.petcoach.co/canigive/dog/tylenol/ ). I recommend calling your Vet regarding that medication as we can't recommend giving it to dogs. I am sorry but if you want to re-post with Ringa's weight we can probably help with the Amoxicillin).
Updated on September 24th, 2025
Unfortunately, we are not permitted to give out drug dosages without a veterinarian - client - pet relationship. If you are seeking this information, I would obtain it through a veterinarian in person or through a veterinary formulary such as Plumb's or Merck. Hope this makes sense.
Updated on September 24th, 2025
I'm so sorry to hear that Kennedy is not feeling well. There are a number of potential side effects to SMZ TMP and they can often occur after being on the antibiotics for a period of weeks. I am attaching more information about that below. https://www.veterinarypartner.com/Content.plx?P=A&S=0&C=0&A=617 So, I would recommend contacting your veterinarian and see what they would recommend for Kennedy at this point. They may want to do a recheck exam on Kennedy or maybe even change her antibiotics. Good luck! I hope that was helpful and that Kennedy feels better soon. Thanks for using PetCoach.
Updated on September 24th, 2025