NexGard vs. Simparica: Which Flea and Tick Preventative Is Safer?
Flea and tick prevention is crucial for maintaining your dog’s overall health and protecting your household from potentially dangerous parasites and the diseases they carry. Two commonly recommended options by veterinarians are
NexGard and
Simparica, both of which are oral, chewable tablets that offer monthly protection. But when it comes to safety, how do they compare?
Understanding the Purpose of Flea and Tick Preventatives
Fleas and ticks are more than just pests—they can cause serious health problems such as:
- Severe itching and dermatitis
- Allergic reactions
- Anemia from blood loss
- Abscesses and skin infections
- Neurological issues like paralysis
- Disease transmission (Lyme disease, anaplasmosis, Rocky Mountain spotted fever)
Using a veterinarian-approved preventative year-round significantly reduces these risks.
NexGard: Safety and Effectiveness
NexGard is an FDA-approved oral medication that protects dogs from fleas and ticks for a full month. Its active ingredient,
afoxolaner, targets the nervous system of parasites, effectively killing them upon ingestion. Key aspects of NexGard include:
- Prescription-only, ensuring professional diagnosis and dosage
- Suitable for dogs 8 weeks and older, and over 4 pounds
- Potential side effects include vomiting, lethargy, or seizures in predisposed dogs
Simparica: Safety and Effectiveness
Simparica, like NexGard, is an oral prescription medication that protects against fleas and ticks. Its active ingredient is
sarolaner, a compound in the isoxazoline class. Notable features include:
- Effective for 5 weeks, offering a longer window of protection
- Approved for dogs 6 months and older, and over 2.8 pounds
- Known side effects are similar to NexGard, including potential neurological events
Which Is Safer?
There is no definitive answer as both medications are generally safe and effective when administered correctly. However, safety depends on several individual factors:
- Age and weight of the dog
- Presence of medical conditions such as a history of seizures
- Genetic predispositions, like the MDR-1 gene mutation in some breeds
- Lifestyle factors such as swimming or frequent bathing (which can influence topical product decisions, though less relevant for oral treatments)
While both NexGard and Simparica are from the same class of drugs (isoxazolines), individual dogs may respond better to one than the other.
Veterinary Guidance is Key
It's critical to consult your veterinarian before choosing any flea and tick preventative. A vet can assess your pet’s individual health profile, environment, and exposure risks to prescribe the safest and most effective option. Vets also guide on proper dosage and administration to help avoid adverse reactions.
Other Considerations for Safety
When evaluating safety:
- Never mix products or DIY treatments with prescriptions
- Read all product labels carefully for dosage and contraindications
- Monitor your dog for any signs of adverse effects like vomiting, tremors, or behavioral changes
- Avoid using canine-specific products on cats, particularly with ingredient classes toxic to felines
Conclusion: NexGard or Simparica?
Ultimately, both
NexGard and
Simparica are safe and effective options when prescribed and dosed appropriately. If your dog has had no prior medical issues, either product can provide excellent parasite protection.
However, because dogs are individuals, their reactions can vary. That’s why clinical guidance from a licensed veterinarian is essential to make the safest choice for your pet’s well-being.
Proper and consistent flea and tick prevention not only protects your dog but also shields your home and loved ones—especially since some diseases can be transmitted to humans. Make parasite prevention a priority—year-round, tailored, and vet-approved.
