Brand: CANIMAX Palatable Allwormer for DOGS

Company: VIRBAC

FORMULATION: «tablets» for oral administration; may be chewable, flavored, coated, etc, depending on the country


    • small dogs: 50 mcg/tablet
    • medium dogs: 100 mcg/tablet
    • large dogs: 200 mcg/tablet
    • small dogs: 112.5 mg/tablet
    • medium dogs: 225 mg/tablet
    • large dogs: 450 mg/tablet
    • small dogs: 25 mg/tablet
    • medium dogs: 50 mg/tablet
    • large dogs: 100 mg/tablet

CHEMICAL CLASS of the active ingredient(s):


PARASITES CONTROLLED* (spectrum of activity):


  • For small dogs: 1 tablet every 5 kg bw (equivalent to 10 mcg/kg abamectin; 22.5 mg/kg oxibendazole; 5 mg/kg praziquantel)
  • For medium dogs: 1 tablet every 10 kg bw (equivalent to 10 mcg/kg abamectin; 22.5 mg/kg oxibendazole; 5 mg/kg praziquantel)
  • For large dogs: 1 tablet every 20 kg bw (equivalent to 10 mcg/kg abamectin; 22.5 mg/kg oxibendazole; 5 mg/kg praziquantel)

* Can be slightly different in some countries: read the product label!


  • LD50 (acute oral) in rats: n.a. for the tablets. 10 mg/kg for abamectin; >10000 mg/kg for oxibendazole; 2840 mg/kg for praziquantel
  • Estimated Hazard Class according to the WHO: not applicable for veterinary medicines

Suspected poisoning? Read the article on abamectin safety and/or oxibendazole safety and/or praziquantel safety in this site.

Never use on cats tablets approved only for use on dogs, and vice-versa. Never use on small dogs tablets approved for large dogs. Learn more about tablets and their safety.

WARNING 1! All heartworm preventatives contain macrocyclic lactones, (e.g. abamectin, ivermectin, milbemycin oxime, moxidectin, selamectin) which must be handled very carefully on dogs. The reason is that dogs of some breeds do not tolerate macrocyclic lactones or other medicines (e.g. emodepside) that can cross the blood-brain barrier. They can suffer more or less serious adverse effects if treated at dose rates slightly higher than the recommended ones. Consequently dosing must be as accurate as possible. This is the case for Collies and related breeds, which have a mutation in the MDR-1 gene that affects the blood-brain barrier and makes it more permeable to such compounds than in dogs without this mutation. Besides Collies, other dog breeds have shown similar problems, although the MDR-1 mutation has not been confirmed in all of them. The breeds more affected by this mutation are (% frequency): Collie (70%), Long-haired Whippet (65%), Australian Shepherd (50%, also mini),  McNab (30%), Silken Windhound (30%), English Shepherd (15%), Shetland Sheepdog (15%), English Shepherd (15%), German Shepherd (10%), Herding Breed Cross (10%). Other less affected breeds are: Old English Sheepdog, Border Collie, Berger Blanc Suisse, Bobtail, Wäller. The only way to be sure that a dog breed is affected by this mutation or not, is to test for it. As more dogs are tested it is likely that the mutation is discovered in other breeds, or that the frequencies change.

WARNING 2! Heartworm preventatives stop development of microfilariae to adult worms but do not cure infections with adult worms. These preventative medicines are different from those curative anthelmintics that kill the adult worms. But preventatives may kill a few adult worms. If this happens, such dead worms may block lung vessels, which can be seriously harmful, even fatal for the pet. Consequently, heartworm preventatives are usually not administered to pets that are already infected with adult worms (hence the need for periodic diagnostic tests), because the risk of serious complications is real. The infection has first to be treated with adequate curative anthelmintics before preventative products are administered. This is however not trivial, and also risky for the same reason.

For these reasons, heartworm prevention should always be done under the supervision of a veterinary doctor.

Click here to learn more on heartworms.

You may be interested in the following articles in this site dealing with the general safety of veterinary products:


Risk of resistance development? YES, but still low in heartworm microfilariae (Dirofilaria spp)

There are reports of resistance or tolerance of heartworm microfilariae (Dirofilaria spp) to ivermectin and other macrocyclic lactones in the USA (mainly in the South), probably including moxidectin as well. This has happened after about 20 years of very intensive use of such compounds there. This may happen elsewhere as well. Currently there are no other once-a-month treatments for heartworm prevention other than those containing macrocyclic lactones.

There are no reports on resistance of tapeworms to praziquantel.

Learn more about resistance and how it develops.


Are the active ingredients of this product ORIGINAL* or GENERICS**?

  • Abamectin: GENERIC (introduced in the 1980s)
  • Oxibendazole: GENERIC (introduced in the 1970s)
  • Praziquantel: GENERIC (introduced in the 1970s)

*Meaning that they are still patent protected and generics are not yet available
**Meaning that they have lost patent protection and may be acquired from manufacturers of generic active ingredients other than the holder of the original patent.

COUNTRIES where this product is marketed: AUSTRALIA
GENERIC BRANDS available? YES, in some countries.

Click here to learn more about GENERIC vs. ORIGINAL drugs.


CANIMAX Palatable Allwormer for DOGS from VIRBAC is a generic once-a-month heartworm preventative effective also against roundworms and tapeworms.

Abamectin is a broad-spectrum parasiticide effective against numerous parasites, both internal (e.g. heartworms, roundworms) and external (e.g. mites, lice). It was introduced in the 1980s and is considered as the "cheap" macrocyclic lactone. It is less potent and more toxic than ivermectin and other macrocyclic lactones but is often "good enough", although usually with a slightly narrower spectrum of efficacy and shorter protection periods than other macrocyclic lactones. At the dose administered in this product it is effective only against heartworm microfilariae, not against roundworms. It has no efficacy whatsoever against tapeworms and flukes. Usage of abamectin in pets is very scarce because other macrocyclic lactones are usually preferred (e.g. ivermectin, milbemycin oxime, etc.). Interestingly abamectin is widely used in livestock in Australia and New Zealand but not at all in the EU, the USA and Canada. As for other macrocyclic lactones, abamectin has no efficacy whatsoever against tapeworms and flukes.

Immature heartworms are transmitted to pets by infected mosquitoes that inject microfilariae (i.e. immature heartworms) during their blood meal. These microfilariae then migrate through the pet's tissues towards the blood vessels. At the dose administered ivermectin kills the migrating microfilariae in the tissues of the pets, but normally not the adult heartworms in the blood vessels.

Oxibendazole is a veteran benzimidazole introduced in the 1970s (by SMITH KLINE → PFIZER→ ZOETIS) that is rather scarcely used in pets, horses or ruminants. It is a broad-spectrum anthelmintic effective against roundworms in the gut and the lungs, but not against those in the skin. It has no efficacy whatsoever against external parasites. It is scarcely to moderately used in pets and horses. Usage in livestock is marginal. It is not used in agriculture

Praziquantel is a veteran isoquinoline anthelmintic introduced in the 1970s (by BAYER). It is still the most effective and most vastly used parasiticide against tapeworms, but without any efficacy against roundworms, fleas or ticks. Praziquantel adds efficacy against tapeworms (Dipylidium caninumTaenia spp, etc.) but has no efficacy whatsoever against roundworms, hookworms or whipworms. It is the anthelmintic most vastly used against tapeworms in pets and horses. There are hundreds of antiparasitic brands for pets & horses containing praziquantel. Usage in livestock is rather modest.

Oxibendazole and praziquantel have no residual effect, i.e. they act against the worms during a few hours after administration but are quickly metabolized and excreted. For this reason treatment must often be repeated for certain indications.

For an overview and a list of the most popular pet wormers click here.


This article IS NOT A PRODUCT LABEL. It offers complementary information that may be useful to veterinary professionals and users that are not familiar with veterinary antiparasitics. 

Information offered in this article has been extracted from publications issued by manufacturers, government agencies (e.g. EMEA, FDA, USDA, etc.) or in the scientific literature. No guarantee is given on its accuracy, integrity, sufficiency, actuality and opportunity, and any liability is denied. Read the site's DISCLAIMER.

In case of doubt contact the manufacturer or a veterinary professional.