Which Dogs Should Avoid NexGard PLUS?
NexGard PLUS is a popular monthly oral medication designed to protect dogs from multiple parasites, including fleas, ticks, heartworm disease, roundworms, and hookworms. While it is widely used and generally deemed safe for most dogs, there are important precautions every pet owner should be aware of before administering this treatment.
Approved Usage for NexGard PLUS
NexGard PLUS is specifically approved for use in:
- Puppies and dogs at least 8 weeks old
- Weighing at least 4 pounds
The medication is designed for dogs within specific weight categories, ensuring accurate and effective dosing. It's available in chew sizes based on dog weight: 4-8 lbs, 8.1-17 lbs, 17.1-33 lbs, 33.1-66 lbs, and 66.1-132 lbs. Dogs over 132 lbs require a combination of chewables.
Dogs That Should Not Take NexGard PLUS
Despite its effectiveness, not all dogs are suitable candidates for this medication. Below are categories of dogs that should not take or should only use NexGard PLUS with veterinary supervision:
- Dogs with seizure history or neurologic disorders: NexGard PLUS contains afoxolaner, part of the isoxazoline class of drugs, which has been linked to neurologic side effects including tremors, ataxia (loss of control of body movements), and seizures. These effects have occurred even in dogs with no previous seizure history, but those with known neurologic conditions are at particularly high risk.
- Breeding, pregnant, or lactating dogs: The safety of this medication has not been evaluated in these dogs. Until further evidence is available, it's advisable to avoid using NexGard PLUS in dogs that are pregnant, nursing, or used for breeding.
- Dogs with known allergic reactions: If a dog has shown adverse reactions to afoxolaner, moxidectin, or pyrantel in the past, NexGard PLUS should be avoided. Instead, alternative parasite treatments should be discussed with a veterinarian.
- Dogs under 4 pounds or younger than 8 weeks: These dogs fall below the approved administration threshold, and using NexGard PLUS on them is not recommended, as safety and efficacy in this group are undetermined.
Health Precautions and Tests Before Starting
- Heartworm testing is essential before starting NexGard PLUS. The medication is designed to prevent heartworm disease by killing larvae, but it is not effective against adult heartworms. Administering NexGard PLUS to a dog already infected with adult heartworms can be ineffective and potentially harmful.
- Dogs should be regularly monitored for gastrointestinal signs (vomiting, diarrhea, itchy skin) and signs of neurologic issues (tremors, disorientation) after starting the medication.
Potential Side Effects
In clinical trials, the most common side effects observed from NexGard PLUS were:
- Vomiting
- Diarrhea
- Lethargy
- Itching
While most reactions were mild and temporary, more severe reactions like seizures require immediate veterinary attention.
Medication Interactions
NexGard PLUS has been studied for use alongside commonly administered medications including:
- Vaccines
- Antibiotics
- NSAIDs (non-steroidal anti-inflammatory drugs)
- Antiparasitics
- Steroids
There were no adverse interactions noted, but any additional medications should still be disclosed to your vet before administering NexGard PLUS.
Safe Administration Tips
- Ensure your dog consumes the entire chew
- If vomiting occurs within two hours, re-dose with another chew
- Do not store half-chewed or broken portions — administer a fresh chewable instead
Importance of Annual Vet Check-Ups
Dogs should be tested annually for heartworm infections and undergo routine wellness checks. Your vet will assess your dog’s overall health, monitor for side effects, and recommend the most appropriate preventative care regimen.
Conclusion
NexGard PLUS offers broad-spectrum protection against several common canine parasites in a convenient monthly chews. However, dogs with certain medical histories or physical conditions should avoid it or use it only under a vet’s close supervision. Always consult your veterinarian before starting, stopping, or changing your dog’s parasite prevention routine.
