Panacur for Dogs: Dosage, Side Effects, and Where to Buy

Name: Panacur for Dogs: Dosage, Side Effects, and Where to Buy
Creator: Dr. Zubair Khalid

By Dr. Zubair Khalid, DVM, MS, PhD · 2026-10-03

Panacur for dogs dosage is based on your dog's body weight and the parasite being treated, so the exact amount comes from your veterinarian, not a one-size-fits-all label. Most dogs take fenbendazole, the active drug in Panacur, for 3 to 5 days for common worms, though giardia and some other infections need longer treatment. This article is educational and is not a substitute for veterinary diagnosis or treatment.

Quick Answer

Panacur's active ingredient is fenbendazole, a dewormer that treats roundworms, hookworms, whipworms, and giardia in dogs.
Your veterinarian calculates the dose from your dog's weight in kilograms and the specific parasite, so never guess the amount.
The liquid and the granules are both dosed by weight, and the liquid is often easier for small dogs and puppies.
Most side effects are mild (vomiting, diarrhea, drooling), but serious reactions are possible and warrant a call to your vet.
Panacur is available over the counter in some forms, but a confirmed diagnosis and correct dose still matter for a good outcome.

What Panacur Is and What Veterinarians Use It For

Panacur is a brand name for fenbendazole, a broad-spectrum deworming medication used in dogs and many other animals. Veterinarians prescribe or recommend it to clear intestinal parasites, most commonly roundworms, hookworms, and whipworms. It is also used to treat giardia, a microscopic parasite that causes diarrhea and can be stubborn to eliminate.

Fenbendazole works against several life stages of these parasites, which is why a full course matters. Giving one dose and stopping early often leaves immature worms behind, and the infection returns. Your veterinarian will tell you how many days your dog needs based on what was found in a fecal test or what symptoms your dog has.

Panacur comes in two main forms for dogs: a liquid suspension and granules that you mix into food. Both contain fenbendazole, and both are dosed by weight. Some owners also ask about the paste made for horses, but that product is not dosed for dogs and should not be substituted without veterinary guidance.

How Fenbendazole Works

Fenbendazole interferes with the parasite's ability to use energy and build the structures it needs to survive. In simple terms, it starves the worm or giardia organism from the inside, and the parasite dies or is cleared from the gut. Because the drug acts on the parasite and not on your dog's own cells, it is generally well tolerated when given at the correct dose.

The medication stays in the gut for much of its action, which is helpful because most of these parasites live in the intestinal tract. That also means the drug needs to be given consistently for the full course so that newly hatched or newly exposed parasites are killed as they appear.

Panacur for Dogs Dosage: The Basics

Who Decides the Dose

Your veterinarian decides the dose. Two things drive it: your dog's weight and the parasite being treated. A puppy with roundworms and an adult dog with giardia may get different total amounts and different treatment lengths even if they weigh the same. This is why a fecal test and an exam matter before you start treatment.

Weigh your dog accurately, ideally at the clinic. Guessing a weight from memory can lead to underdosing, which lets the infection persist, or overdosing, which raises the risk of side effects. If you are treating multiple dogs, dose each one separately based on its own weight.

How Panacur Is Given

The liquid suspension is measured with an oral syringe or dosing syringe and given by mouth. Many owners squirt it toward the back of the tongue or mix it with a small amount of food. The granules are sprinkled over a small portion of food and mixed in well. Give the full amount your veterinarian prescribed, and make sure your dog eats all of the medicated food.

For giardia, treatment often runs longer than the standard worm course. Your veterinarian may also recommend a follow-up fecal test to confirm the infection has cleared. If your dog has diarrhea, your vet may suggest supportive care alongside the dewormer. You can read more about gut support in this guide to probiotic supplements for dogs.

Panacur for Dogs Liquid Dosage

The liquid form is popular for puppies and small dogs because it is easy to measure and easy to swallow. The dose is still based on weight in kilograms and the parasite being treated, so follow the amount your veterinarian gives you. Shake the bottle well before each dose, because the medication can settle.

Do not use a kitchen spoon to measure the liquid. Spoon sizes vary, and the difference can be large for a small dog. Use the dosing syringe that comes with the product or one your veterinarian provides. If you are unsure how much to draw up, call the clinic and ask them to confirm the number in milliliters.

Panacur for Dogs Dosage Chart

A dosage chart is only useful if it matches your dog's weight and the specific parasite. Because the correct amount depends on both, a general chart cannot replace your veterinarian's instructions. Ask your clinic to write the dose on the label or on a discharge sheet, including the amount, the form (liquid or granules), and how many days to give it.

If your dog is between two weight ranges on any chart, do not round down. Underdosing is a common reason deworming fails. Call your veterinarian and confirm the correct amount for your dog's exact weight.

Missed Doses

If you miss a dose, give it as soon as you remember, unless it is almost time for the next one. In that case, skip the missed dose and continue with your regular schedule. Do not double up to make up for a missed dose, because that increases the chance of stomach upset. If you miss more than one dose, call your veterinarian for guidance on whether to restart the course.

Panacur for Dogs Side Effects

Most dogs handle fenbendazole well. When side effects happen, they are usually mild and short lived. The table below covers the common and the serious reactions owners ask about.

Side effect	How common or serious	What to do
Vomiting	Common and usually mild	Withhold food briefly, offer water, and call your vet if it repeats
Diarrhea	Common and usually mild	Keep water available and call your vet if it lasts more than a day
Drooling or lip smacking	Common after liquid dosing	Give with a small treat or food and watch for improvement
Loss of appetite	Possible and usually mild	Offer small bland meals and call your vet if it continues
Lethargy	Less common, may be serious	Contact your veterinarian the same day
Hives, facial swelling, trouble breathing	Rare but serious	Treat as an emergency and seek care immediately
Bloody stool or persistent vomiting	Serious	Call your veterinarian or an emergency clinic right away

If your dog vomits soon after a dose, the medication may not have been absorbed. Do not automatically repeat the dose. Call your veterinarian and describe what happened, including how long after dosing the vomiting started.

Who Should Not Take Panacur and Drug Interactions

Panacur is not right for every dog. Tell your veterinarian about all medications, supplements, and health conditions before you start. Dogs who are pregnant, nursing, very young, or underweight need a veterinarian's specific guidance, because the dose and timing may change.

Fenbendazole can interact with other medications, so a full medication list matters. Do not combine Panacur with another dewormer unless your veterinarian tells you to. If your dog takes a medication for another condition, ask your vet whether the two can be given together or should be spaced apart.

If your dog has a history of liver problems or has had a bad reaction to a dewormer before, say so at the visit. Your veterinarian may choose a different product or adjust the plan. For dogs on multiple medications, keeping a written list on your phone makes these conversations faster and safer.

Overdose and When to Call for Help

Giving too much Panacur can cause vomiting, diarrhea, and lethargy. If you think your dog received more than the prescribed amount, call your veterinarian right away. If the clinic is closed, contact an animal poison control service. The ASPCA Animal Poison Control Center can be reached at (888) 426-4435, and the Pet Poison Helpline is available at (855) 764-7661. A consultation fee may apply.

Have the product container ready when you call. The person helping you will want to know the strength of the product, how much your dog weighs, and how much was given. Do not wait for symptoms to appear before you call, because early guidance is safer than watching and hoping.

Panacur for Dogs Over the Counter and Where to Buy

Panacur is available over the counter in some forms and sizes, which surprises many owners. You can find it at pet supply stores, some farm and feed stores, and online retailers. The catch is that the over-the-counter label is written for general use, and it may not match your dog's specific diagnosis or weight.

Where you buy matters less than getting the right product and the right dose. If you buy Panacur for dogs over the counter, read the label carefully to confirm it is the dog formulation and the correct strength. If the label instructions do not match what your veterinarian recommended, follow your veterinarian.

Your veterinarian can also dispense or prescribe Panacur directly, which is often the simplest path because the dose is calculated for you. If cost is a concern, ask the clinic about the total price of the full course before you decide. Panacur for dogs cost varies by product form, size, and where you buy it, so compare the full treatment cost, not just the bottle price.

For dogs with confirmed giardia or stubborn worm infections, the treatment plan often includes more than one medication or a longer course. This related guide covers the details of Panacur fenbendazole for dogs, including roundworm and giardia dose and duration. If your dog is also being treated for itching or allergies, check with your vet before adding anything new, and review how other common medications are dosed, such as this Apoquel oclacitinib daily dose chart for dogs.

Limitations and When to Contact a Veterinarian

No article can tell you the right dose for your individual dog. Your dog's weight, age, health history, and the parasite involved all change the plan, and only a veterinarian who examines your dog can make that call.

Contact your veterinarian the same day if your dog vomits repeatedly, has diarrhea that lasts more than a day, refuses food, or seems unusually tired after starting Panacur. These signs are often mild, but they deserve a phone call so your vet can decide whether to adjust the plan.

Go to an emergency clinic now if your dog has trouble breathing, swelling of the face or muzzle, hives, collapse, or repeated vomiting with blood. These are signs of a serious reaction and should not wait until morning.

Schedule a routine visit if your dog finished treatment but still has soft stool, a pot belly, or visible worms in the stool. A follow-up fecal test can confirm whether the infection cleared. If you have other dogs or cats at home, ask whether they also need testing or treatment, because some parasites spread easily between pets.

Frequently Asked Questions

How long does Panacur take to work in dogs?

Most dogs start passing dead worms within a day or two of the first dose, and symptoms like diarrhea often improve within a few days. The full course still needs to be finished even if your dog looks better, because immature parasites can survive early doses. Your veterinarian may recommend a follow-up fecal test after treatment ends.

Can I give Panacur to my dog without seeing a vet?

You can buy some Panacur products over the counter, but treating without a diagnosis is risky. Different parasites need different treatment lengths, and some causes of diarrhea are not worms at all. A fecal test is quick and tells your veterinarian exactly what to treat.

Is Panacur safe for puppies?

Panacur is commonly used in puppies, but the dose and timing depend on the puppy's age and weight. Very young puppies need a veterinarian's specific plan, and some products are not labeled for the youngest dogs. Always confirm with your vet before deworming a puppy at home.

What should I do if my dog throws up after taking Panacur?

Do not repeat the dose on your own. Call your veterinarian and report how long after dosing the vomiting happened and how much your dog ate. Your vet will decide whether to redose, switch forms, or change the plan.

Do I need to treat my other pets too?

Often yes, especially if one dog has roundworms or giardia, because these parasites spread through shared soil, water, and toys. Your veterinarian can advise which pets need testing or treatment. Cleaning bedding, bowls, and yard areas also helps prevent reinfection.