Which Dogs Should Not Take NexGard PLUS?
NexGard PLUS is a powerful monthly chewable medication that protects dogs from fleas, ticks, heartworms, roundworms, and hookworms. While it provides many health benefits, it's important to understand that not all dogs are suitable candidates for taking NexGard PLUS. Pet owners should carefully evaluate their dog’s health history before beginning treatment.
1. Dogs With Neurologic Disorders
Dogs that have a history of seizures or neurologic disorders should be prescribed NexGard PLUS with explicit caution. One of NexGard PLUS's active ingredients, afoxolaner, belongs to the isoxazoline class, which has been associated with neurological side effects in some dogs, including:
- Tremors
- Ataxia (loss of coordination)
- Seizures (even in dogs without a history of them)
If your dog has previously experienced any unusual neurologic episodes, it is crucial to consult your veterinarian to determine whether NexGard PLUS is a safe option.
2. Breeding, Pregnant, or Lactating Dogs
The safety of NexGard PLUS has not been evaluated in breeding females, pregnant, or lactating dogs. Because the effects on such dogs are unknown, veterinarians may recommend an alternative form of parasite prevention or opt to delay usage until after the nursing or pregnancy period.
3. Dogs Under Minimum Age or Weight
NexGard PLUS is approved for dogs and puppies 8 weeks of age and older, weighing at least 4 pounds. It should not be administered to dogs that do not meet these basic criteria, as the safety and effectiveness have not been established in younger or lighter dogs.
4. Dogs With Active Heartworm Infections
Before starting NexGard PLUS, dogs should be tested for existing heartworm infection. While the medication prevents heartworm disease by targeting the larvae, it’s not effective against adult heartworms (Dirofilaria immitis). Using NexGard PLUS on infected dogs may cause complications and will not treat existing infections.
5. Dogs With Certain Medication Interactions
While clinical studies show that NexGard PLUS can be used with most commonly administered medications (such as vaccines, antibiotics, and pain relievers), any new treatment plan should be discussed with a veterinarian to evaluate potential drug interactions. Special care should be taken when used with other neurological medications.
6. Dogs With Known Allergic Reactions
In rare cases, some dogs may be allergic to ingredients in NexGard PLUS. Common signs of adverse reactions include:
- Vomiting
- Diarrhea
- Itching
- Lethargy
If your dog displays any of these symptoms after initial dosing, discontinue use and seek veterinary help immediately.
Precautionary Guidelines for Pet Owners
- Monitor your dog for 24–48 hours after administration
- Contact your veterinarian if your dog exhibits unusual behavior or symptoms
- Give the full chewable dose on the same date each month
- Do not split doses across multiple days or store partially used chews
The Importance of Veterinary Consultation
No medication is one-size-fits-all. Before beginning, continue, or discontinue NexGard PLUS, it is best practice for pet owners to consult with a licensed veterinarian. A comprehensive health assessment can determine:
- Heartworm status through a blood test
- Compatibility with other treatments or medications
- Appropriateness based on your dog’s age, weight, and overall health
Summary
NexGard PLUS offers powerful preventative health benefits, but it is not suitable for every dog. Dogs with neurologic issues, pregnant or lactating dogs, young puppies under 4 pounds or 8 weeks, and those with confirmed heartworm infections require special consideration. Awareness and proper veterinary guidance are essential to ensure a safe and effective parasite prevention plan for your beloved pet.
