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Every once in awhile, your veterinarian gives you unpleasant news. Sometimes, that news sounds like this: “Your dog has worms.”

Nobody wants to hear that her dog has internal parasites, but worms in dogs are more common than you might think. They are also usually treatable. One of the medications veterinarians frequently prescribe for dogs with worms is Panacur, a deworming medication used to treat several species of canine parasites.

What Is Panacur?

Panacur is the brand name of an oral deworming medication with the active ingredient fenbendazole. It is used to treat internal parasites in domestic animals, including dogs, cats, horses, and livestock. In dogs, Panacur is most often used to treat hookworm, roundworm, tapeworm (Taenia), and whipworm infections, although it is important to note that Panacur is not effective against Dipylidium tapeworms.

In addition to these worms, Panacur (fenbendazole) is approved in Europe to treat Giardia in dogs and is sometimes used off-label in the U.S. to deal with Giardia infections. It is also occasionally used off-label to combat lungworm infections.

How Does Panacur Work?

Deworming medications work in different ways to eliminate parasites. Some target specific life stages, while others attack the biological processes of the parasite. Fenbendazole kills parasites by binding to tubulin (a type of protein), which interferes with the parasites’ ability to form microtubules, which combine to form the structure of the worm cells.

So how do you introduce this parasite eliminator into your dog’s system? Panacur is given orally, either in granules, a suspension, or a paste. Talk to your veterinarian about the best formulation for your dog and for tips about how to properly administer a dewormer.

Side Effects of Panacur for Dogs

Panacur is generally considered a very safe medication and is one of the safest dewormers on the market. Its active ingredient has a selective affinity for parasitic tissue, which means it usually ignores your dog’s body tissues unless given in very high doses, and even then dogs can tolerate doses up to 100 times higher than recommended. Manufacturers list vomiting as a possible side effect, and some formulations, like Panacur Plus, contain other medications, such as ivermectin and praziquantel, which can have more serious side effects.

Even though the drug is generally safe, you still need to exercise caution. Some dogs may have an allergic reaction to the dying parasites themselves. Watch out for symptoms of an allergic reaction in dogs, which include facial swelling, itchiness, hives, diarrhea, vomiting, seizures, shock, pale gums, cold limbs, and coma. You should also talk to your vet about giving Panacur to pregnant dogs. Your veterinarian may have to adjust the dosage, and Panacur is not recommended for puppies under six weeks old.

How Much Panacur Should I Give My Dog?

When it comes to the dosage and duration of Panacur or any other medication, talk to your veterinarian. While the Internet is a great source of initial information about drug dosages, your veterinarian may have his or her own reasons for adjusting your dog’s dose and duration. These changes are based on your dog’s medical history or condition, and an inaccurate dosage and duration estimate could harm your dog and lead to parasite resistance.

The dosage and duration of the drug also depends on the intended use. Your veterinarian might prescribe a different dosage for Giardia than he would for roundworms, for instance, so make sure you follow his instructions to ensure that your dog receives the full benefit of the medication.

For more information about Panacur for dogs, consult your veterinarian.

This article is intended solely as general guidance, and does not constitute health or other professional advice. Individual situations and applicable laws vary by jurisdiction, and you are encouraged to obtain appropriate advice from qualified professionals in the applicable jurisdictions. We make no representations or warranties concerning any course of action taken by any person following or otherwise using the information offered or provided in this article, including any such information associated with and provided in connection with third-party products, and we will not be liable for any direct, indirect, consequential, special, exemplary or other damages that may result, including but not limited to economic loss, injury, illness or death.