Best Dewormer for Puppies in 2026: Top 5 Picks

Reviewed by Tom Smith

Disclaimer: This article is a general guide only and is not veterinary advice. Always consult a qualified vet before giving any treatment to your puppy. If you think your pet has worms, get professional care quickly.

Recent studies show gut parasites are rising in North America, even in young dogs^[1]. That is a concern for puppies, which face a higher risk than adult dogs and can get serious health problems if left untreated.

This guide compares the best dewormer for puppies in 2026.

We reviewed five top dewormers. We looked at what each one treats, who it fits best, and what vets recommend.

Quick Comparison: Best Dewormers for Puppies

Not sure which dewormer fits your puppy? Use the list below as a quick guide. Then read the full review for more detail.

Disclaimer: Always check fit with your vet before starting any deworming treatment. Not all treatments suit all dogs.

Why Deworming Puppies Matters

Not every puppy will get worms, but most will meet intestinal parasites before adulthood. Roundworms and hookworms are among the most common parasites in dogs under one year old. Research also suggests that puppies under six months are among the least likely to get preventive deworming treatment.^[2]

Untreated worms can cause problems from mild to severe. Infected puppies may have poor weight gain, a dull coat, diarrhea, vomiting, or anemia. In worse cases, puppies infected before birth or through their mother's milk can develop fatal anemia as early as one to two weeks old, often before their first vet visit.

Common Worm Types

There are five common worm types in puppies:

• Roundworm: The most common gut worm. It may account for about 50% of infestations. Roundworms grow three to five inches long and take nutrients from your pet's food.
• Hookworm: Too small to see with the naked eye. Hookworm infestations can cause paleness and poor appetite. Severe cases can be fatal in young puppies, so suspected infection needs fast vet care.
• Tapeworm: Usually spread by infected fleas or rodents. Tapeworms live in the large intestine, and their eggs pass in feces. Small white flakes or rice-like pieces in your puppy's stool are a key sign.
• Whipworm: Often spread through dirty feces or soil. It can cause bloody stool in bad cases, but some mild outbreaks show no signs.
• Heartworm: Spread by mosquito bites, heartworms can grow to 30 cm long. Signs include coughing, tiredness, breathing trouble, and weight loss. Heartworm usually does not show up in puppies until 6 months of age. Note: heartworm is not a gut parasite.

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What Treatment Is Right for Me?

The right puppy dewormer depends on your puppy's age, size, health, local parasite risk, and how easy it is to give treatment on time.

For many pet owners, an all-in-one monthly treatment that covers fleas, ticks, and worms fits a busy life and cuts down on separate products. Others prefer a monthly broad-spectrum treatment plus a target product for a parasite such as heartworm. Some dewormers for dogs also suit puppies, but the dose must match your puppy's age and weight. If your puppy is a fussy eater, taste matters too. Most modern dewormers come as chews, tablets, or spot-on products.

The best choice is different for every puppy and every home. Your vet is best placed to suggest the right option based on your puppy's needs and the parasites most common in your area.

Selection Criteria

The five products in this guide were chosen based on five points: coverage, fit for young puppies, ease of use, length of coverage, and price. All active ingredient and product details come straight from the maker's site. Where needed, we checked the info against dosing guides.

1. Drontal Allwormer Tablets for Small Dogs — Best for Intestinal Worm Treatment

Drontal All Wormer for Small Dogs is a good pick if you want to target gut worms. It also uses a different dosing schedule from the other products on this list.

Parasites Covered	Roundworm, Hookworm, Whipworm, Tapeworm
Active Ingredients	Praziquantel, Pyrantel Embonate, Febantel
Form	Tablet — Every 3 Months
Suitable For	Puppies up to 20lb
Minimum Age	6 Weeks
Prescription Required	Yes*

Why We Picked It: It is the only product here that covers three months, which makes dosing easier. The tablets are also tasty, and the 3-month plan can help keep long-term costs down.

What It Treats: Drontal Allwormer Tablets target the four common gut parasites: roundworm, hookworm, whipworm, and tapeworm. Its tablet form, with praziquantel, febantel, and pyrantel embonate, gives longer coverage than monthly chews.

Pros	Cons
Covers four intestinal parasite types	Does not cover Heartworm, fleas, or ticks
Three monthly coverage	May require multiple tablets depending on animal size
Low cost	Prescription Required*

Best For: Owners who struggle with monthly dosing or the cost of all-in-one treatments and just need worm protection.

Look Elsewhere If: You need all-in-one parasite protection or your dog does not take tablets well.

2. NexGard Spectra for Extra Small Dogs 4.4–7.1 lb — Best All-in-One Treatment

If you want a monthly set-and-forget treatment for all types of parasites, NexGard Spectra is a strong choice. It gives monthly coverage for worms, fleas, and ticks.

Parasites Covered	Fleas, Ticks, Roundworm, Hookworm, Whipworm, Tapeworm
Active Ingredients	Milbemycin Oxime, Afoxolaner
Form	Monthly Chew
Suitable For	Puppies up to 7.1lb
Minimum Age	8 Weeks
Prescription Required	Yes*

Why We Picked It: All-in-one treatments are a favorite for busy owners or picky dogs that do not like several treatments each month. The NexGard Spectra range is also one of the best-known parasite prevention products on the market.

What It Treats: NexGard Spectra protects against fleas, ticks, and the four major gut worms.

Pros	Cons
Covers fleas, ticks and the four intestinal parasite types	Does not cover Heartworm
Highly palatable	Does not include comprehensive tapeworm protection
Monthly dosing	Prescription Required*

Best For: Dogs that are picky eaters and owners who want one treatment for all parasites.

Look Elsewhere If: You need heartworm protection or prefer a treatment that is not monthly.

3. Interceptor Spectrum — Best for Broad-Spectrum Heartworm and Intestinal Worm Treatment

Interceptor Spectrum offers the broadest parasite coverage on this list. It combines gut worm treatment with heartworm prevention in a single monthly chew.

Parasites Covered	Roundworm, Hookworm, Whipworm, Tapeworm, Heartworm
Active Ingredients	Milbemycin Oxime, Praziquantel
Form	Monthly Chew
Suitable For	Puppies up to 8.8lb
Minimum Age	From 6 Months
Prescription Required	Yes*

Why We Picked It: Few products combine gut worm coverage with heartworm prevention in one dose. For owners who want one product that does it all, Interceptor Spectrum removes the need for separate treatments and makes the monthly routine simpler.

What It Treats: Interceptor Spectrum targets four common gut parasites—roundworm, hookworm, whipworm, and tapeworm—while also preventing heartworm infection. Its two active ingredients, milbemycin oxime and praziquantel, work together to cover a wider range than most single-ingredient products.

Pros	Cons
Covers five parasite types	Not suitable above 8.8lb
Monthly application	Does not cover fleas or ticks
Palatable chew format	Prescription Required*

Best For: Owners of small puppies who want broad monthly parasite coverage, including heartworm, in one product.

Look Elsewhere If: Your puppy weighs more than 8.8 lb or you need flea and tick coverage too.

4. Advocate Spot-On for Puppies & Dogs up to 9 lb — Best for Spot-On/Topical Treatments

For puppies that resist tablets or chews, a spot-on treatment is a practical option. Advocate is applied directly to the skin and gives broad parasite coverage without oral dosing.

Parasites Covered	Roundworm, Hookworm, Whipworm, Heartworm, Oesophageal Worm, Ear Mites, Lice, Fleas
Active Ingredients	Imidacloprid, Moxidectin
Form	Monthly Spot-On
Suitable For	Puppies up to 9lb
Minimum Age	From 7–8 Weeks
Prescription Required	Yes*

Why We Picked It: Of the topical treatments available, Advocate provides the broadest protection, especially for worms and fleas. It is also one of the few worming products that protects against Oesophageal Worm.

What It Treats: Advocate Spot-On targets four common gut parasites, excluding tapeworms, while also preventing heartworm infection. It also covers ear mites, lice, fleas, and Oesophageal Worm.

Pros	Cons
Topical treatment benefits fussy puppies	Can require hospitalisation if ingested by another pet
Broad coverage including mites and fleas	Does not cover ticks
Usable from an earlier age	Prescription Required*

Best For: Owners of fussy puppies who would not otherwise take parasite preventives by mouth.

Look Elsewhere If: You have other pets that lick treated dogs or need tick protection too.

5. Simparica Trio for Puppies 2.8–5.5 lb — Best for Young Puppies

Simparica Trio offers the smallest weight range of the five products on our list. That gives a more tailored formula for young puppies.

Parasites Covered	Roundworm, Hookworm, Whipworm, Tapeworm, Heartworm, Fleas, Ticks
Active Ingredients	Moxidectin, Sarolaner, Pyrantel
Form	Monthly Chewable
Suitable For	Puppies from 2.8–5.5lbs
Minimum Age	From 8 Weeks
Prescription Required	Yes*

Why We Picked It: No other preventive offers protection for such a specific puppy weight range. If you are worried about formulas that are too strong for your puppy, this is a reliable option.

What It Treats: Simparica Trio protects against fleas, ticks, and the four major gut worms.

Pros	Cons
Effective from only four hours after application	Limited coverage for rapidly growing puppies
Broad coverage including tapeworms and heartworms	Only available in a 3-pack
Tailored formulation for smaller puppies	Prescription Required*

Best For: Owners of smaller puppies who want a more tailored formula.

Look Elsewhere If: Your puppy is growing fast during the treatment window.

Can I Get These Products Without a Prescription?

Readers in the United States or Canada may notice that several products in this list need a vet prescription in their region. In Australia, the same products are sold over the counter. As an Australian-based retailer, Smartway Pet Supplies can supply these products under Australian law. Many countries, including the United States and Canada, allow personal import of pet medicines within set limits, which can make access easier.

We suggest checking the import rules for your country before you place an order.

Conclusion

Choosing the right dewormer for puppies comes down to your puppy's needs, your routine, and the parasites most common in your area. Any of the five products above is a strong starting point, but always check fit with your vet before starting treatment. Browse our full range of puppy dewormers at Smartway Pet Supplies.

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Frequently Asked Questions

How do I know which puppy dewormer is the best fit?

The right choice depends on your puppy's age, weight, health status, parasite risk in your region, and how easily you can give the product. For example, Drontal may suit owners focused on intestinal worms and less frequent dosing, while NexGard Spectra or Simparica Trio may suit owners who want flea, tick, and worm coverage. Interceptor Spectrum is a strong option when heartworm prevention is also needed, and Advocate may be better for puppies that refuse oral treatments. Always check the best option with your vet before starting treatment.

Are all dewormers in this guide effective against heartworm?

No. Heartworm coverage varies by product. Interceptor Spectrum and Advocate include heartworm prevention, while Drontal focuses on intestinal worms. NexGard Spectra and Simparica Trio are described here as covering fleas, ticks, and the four main intestinal worms, but check carefully if you need heartworm protection, especially for NexGard Spectra. Because heartworm is spread by mosquitoes and is not a gut parasite, it is important to check product coverage carefully.

What signs might suggest my puppy has worms?

Possible signs include poor weight gain, a dull coat, diarrhea, vomiting, anemia, paleness, poor appetite, bloody stool, or rice-like white pieces in the stool. Some infections may show few or no clear signs, while severe hookworm or early-life infections can be life-threatening. If you think your puppy has worms, get vet care quickly instead of relying on symptoms alone.

Should I choose a tablet, chew, or spot-on treatment?

The best format depends on your puppy and your routine. Tablets such as Drontal may offer longer coverage for gut worms, monthly chews can be convenient for puppies that accept tasty oral treatments, and spot-on products such as Advocate can help when a puppy resists tablets or chews. Consistency matters, so choose a format you can give correctly and on time.

Can I buy these puppy dewormers without a prescription?

It depends on where you live. The article explains that some products needing prescriptions in the United States or Canada are sold over the counter in Australia. Smartway Pet Supplies can supply them under Australian law, but customers should check their own country's import rules before ordering.