For my dog, I wasn't able to afford the exam that checks for all the different types of worms that dogs can attract. However, I did see deworming chewable tablets. Is it harmful to feed a dog these tablets just in case?

Sorry if this is a dumb question.

  • Can you give us a bit more info, whats the brand of tablets and do you see worms in your dogs stool? Sep 7, 2017 at 20:54
  • No, I do not see any worms in my dog's stool. And, I'm not exactly sure which brand to use. There were lots of brands. Hence, I was going to ask what brand I should use, if it was okay to do so.
    – Jonathan
    Sep 8, 2017 at 1:01
  • I forgot to ask, where are you located? Sep 8, 2017 at 1:37
  • I'm located in San Diego. So it's pretty hot and very low humidity.
    – Jonathan
    Sep 8, 2017 at 2:45
  • Maybe it is different here and maybe the agent is different, but in Germany we regulary give our dogs deworming chewable tablets for prevention of getting worms. Sep 8, 2017 at 9:11

2 Answers 2


It is ideal to do a faecal float and smear to look for any eggs or protozoa, before treating. If you would rather just empirically deworm then there are many safe over-the-counter products, but there are also many unsafe over-the-counter products.

For empiric deworming in an adult dog I would recommend a fenbendazole product (such as Panacur) or pyrantel product (such as Nemex).

Fenbendazole will cover for most common internal parasites but is not great for tapeworms, and not for heartworms. Pyrantel will get roundworms and hookworms but not much else.

There is no one product that will get all worms. Certain topical medications like Advantage Multi are good for fleas, heartworms, and some intestinal worms.

Whatever product you use make sure you dose it appropriately.

I recommend you ask your veterinarian about the product you decide to use before giving it to the dog. There are many products out there, and with some over-the-counter products adverse reactions seem to occur with alarming frequency.


When to test for intestinal parasites

The only time we would run a fecal is when a dog has diarrhea, we're very fair with our clients and do not want to waste their money on tests that have a high chance of a negative result especially when our dewormers take out the most common parasites we see.

What dewormer to use

This is very much dependent on your location as risks of parasites will vary from country to country or province to province (state in your case).

In Ottawa we have risk of heartworm disease and lyme disease so all of our dewormers need to focus on heartworm and should be bundled with a flea & tick product.

  • Flea & tick prevention to be given from March until December
  • Heartworm prevention to be given from June until November

We pair up Interceptor (heartworm, roundworm, hookworm, whipworm) with Advantix (Fleas, ticks, black flies, mosquitoes etc.).

If you are not concerned about ticks Advantage Multi (fleas, heartworm, roundworm, hookworm, whipworm, mange) would be a great choice.

Bayer recommends us to use Advantix + Advantage multi but we feel like it's way too much liquid to put on a pet and it's a bit of an overkill.

San Diego I'm not overly familiar with what parasites you have there so call up your local vet and ask them what bugs you have in the area and how many months of the year should you treat for, they shouldn't charge you for asking a question.

In US states that are always hot, flea treatment is a must for 12 months of the year.

In some US states you can pick up some over the counter fenbendazole at farm animal pharmacies without a prescription. I suspect this only applies to states that are known for farming. This will cover your roundworms, whipworms, hookworms, giardia and some tapeworms.

What to stay away from

Anything by Hartz, their products kill pets - most over the counter pet store dewormers aren't 100% effective.


If heartworm disease is prevalent in your area and your dog has not been consistently protected from it it is HIGHLY recommended to test your dog for heartworm disease BEFORE giving heartworm medication. Killing an infestation can cause death to your pet - this should be done under veterinary supervision and guidance.

In Conclusion

At the end of the day your most reliable medications for deworming are provided to you by your DVM, if diarrhea is present a fecal test should be ran to rule out less common protozoa such as giardia and coccidia as treatment will be different.

  • Advantage Multi (imidacloprid + moxidectin) requires a prescription. Advangage (imidacloprid) does not. bayerdvm.com/show.aspx/productdetail/advantage-multi-for-dogs
    – Harry V.
    Sep 8, 2017 at 14:21
  • @HarryV. thanks! Yes! I talked to my boss about it he said the vets in the US were SUPER upset that they started selling it in the stores. Loss of revenue for them. Sep 8, 2017 at 15:33

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