Many dog owners want one product that covers fleas, ticks, heartworm and intestinal worms. NexGard PLUS is a prescription monthly chew designed to do that. This review summarizes what its label covers, possible side effects and safety information. It’s for general information only, and your vet should decide whether it’s right for your dog.
Bottom Line: NexGard PLUS combines three active ingredients to cover fleas, several tick species, heartworm prevention and roundworms and hookworms in a monthly chew. It’s convenient and widely prescribed. It requires a prescription and a heartworm test, and like other isoxazolines, it carries an FDA warning about possible neurologic reactions.
At a Glance
| Feature | Details |
|---|---|
| Type | Prescription monthly chewable |
| Active ingredients | Afoxolaner, moxidectin and pyrantel |
| Covers | Fleas, certain ticks, heartworm prevention, roundworms and hookworms (check current label) |
| Age and weight | Minimum age and weight on the label |
| Prescription | Required |
What It Is and How It Works
NexGard PLUS combines afoxolaner, an isoxazoline that kills fleas and ticks, with moxidectin for heartworm prevention and pyrantel for roundworms and hookworms.
Because it prevents heartworm disease, dogs need a heartworm test before starting and usually once a year after that. Giving a heartworm preventive to a dog that already has heartworms can cause serious reactions.
Chewables avoid the mess of topicals and can’t be washed off by bathing or swimming. Most dogs take them like treats. See heartworm prevention for dogs and comparison of popular pet heartworm medications.
Strengths
- Covers fleas, ticks, heartworm and some intestinal worms in one chew
- Monthly dosing
- Not affected by bathing or swimming
- Most dogs take it easily
- Widely prescribed
Limitations
- Requires a prescription and heartworm test
- Isoxazoline neurologic warning
- Possible stomach upset
- Higher cost than single-purpose products
Treating the Whole Home for Fleas
Flea control works best when you treat the whole household, not just one pet:
| Step | Why it matters |
|---|---|
| Treat every dog and cat in the home | Untreated pets keep the flea cycle going |
| Vacuum floors and furniture often | Removes eggs, larvae and pupae |
| Wash pet bedding in hot water | Kills developing fleas |
| Keep treating on schedule | Pupae can hatch for weeks to months |
| Check for ticks after outdoor time | Even treated dogs can carry ticks briefly |
Most of a flea infestation lives in the environment, not on the pet. Clearing a home can take several months of consistent treatment. See ticks on dogs and battling flea allergy dermatitis.
Safety Notes and Possible Side Effects
- Side effects listed on labels for similar products include vomiting, diarrhea, lethargy, poor appetite and itching.
- Isoxazolines carry an FDA warning about neurologic reactions.
- Dogs need a heartworm test before starting.
- Follow the label’s minimum age and weight.
- Give with food if your vet recommends it, to reduce stomach upset.
In 2018, the FDA alerted owners and vets that isoxazoline products, including afoxolaner, have the potential to cause neurologic adverse reactions such as muscle tremors, unsteadiness and seizures, even in dogs with no history of these problems. These products remain FDA-approved and most dogs don’t have these reactions, but tell your vet if your dog has a history of seizures.
Before You Buy
- Ask your vet about your dog’s parasite risks.
- Make sure your dog has a current heartworm test.
- Tell your vet about any seizure history.
- Give it on the same date each month.
- Watch your dog after the first dose.
Tips for Using It
- Set a monthly reminder on your phone.
- Watch that your dog eats the whole chew.
- Keep doses out of reach, since dogs may eat several if they find them.
Who It Suits
| Good fit if… | Consider something else if… |
|---|---|
| Your vet recommends year-round parasite prevention | Your dog has a history of seizures, unless your vet advises otherwise |
| You want one monthly product | Your dog has an untreated heartworm infection |
| Your dog swims or is bathed often |
Alternatives to Consider
| Option | How it differs |
|---|---|
| Simparica Trio | Another combination chew |
| Credelio plus a heartworm preventive | Separate products |
| Topical combination products | For dogs that won’t take chews |
When to Call Your Vet
Contact your vet if:
- Your dog has tremors, wobbliness or seizures
- Your dog vomits repeatedly or stops eating
- Your dog shows signs of an allergic reaction
Frequently Asked Questions
What does NexGard PLUS protect against?
Its label covers fleas, certain tick species, heartworm disease prevention, and roundworm and hookworm infections. Check the current label for the full list.
Is NexGard PLUS safe?
It’s FDA-approved and widely used. Like other isoxazoline products, it carries a warning about possible neurologic reactions. Discuss your dog’s history with your vet.
What’s the difference between NexGard and NexGard PLUS?
NexGard covers fleas and ticks only. NexGard PLUS adds heartworm prevention and treatment for roundworms and hookworms.
Does my dog need a heartworm test first?
Yes. Dogs should be tested before starting a heartworm preventive and usually yearly after that.
What are common side effects?
Reported side effects for similar products include vomiting, diarrhea, lethargy, reduced appetite and itching. Contact your vet if you notice changes.
Can puppies take NexGard PLUS?
Check the label for the minimum age and weight. Your vet will confirm whether your puppy qualifies.
What if I miss a dose?
Give it as soon as you remember and contact your vet, especially about heartworm protection.
Can I buy NexGard PLUS without a prescription?
No. In the United States, it requires a prescription from a vet.
Pet Health Man is independent and isn’t paid by the brands we review. Product formulas, specifications and prices change, so check the current label or the manufacturer’s information before you buy.
This article is for general information only and isn’t a substitute for professional veterinary advice. If you’re worried about your pet’s health, contact your veterinarian or an emergency animal hospital.
