NexGard vs Simparica: We Asked a Vet (2023 Update)
Updated on
There is a myriad of products available to treat infestations of fleas, ticks, and other ectoparasites in dogs, two of which are NexGard (Afoxolaner) and Simparica (Sarolaner). NexGard is a Boehringer Ingelheim product, while Simparica is from Zoetis. Other products are available within these ranges that have broader spectrums of activity (NexGard Spectra, Simparica Trio), and some that are licensed for use in cats (NexGard Combo), but these are beyond the scope of this article.
The drugs contained in NexGard and Simparica both act to interrupt the normal functioning of the parasites’ nervous systems, thereby killing them. Exposure to either drug requires fleas and ticks to be attached to your dog, and for them to have started feeding off him or her. NexGard and Simparica are both prescription veterinary medicines so your dog will need to be examined at intervals by your veterinarian while using them. It is also possible to purchase the treatments from online veterinary pharmacies, so long as all examination requirements have been fulfilled and you have a written prescription from your veterinarian.
Both NexGard and Simparica are popular routine parasitic treatments for dogs targeting fleas, ticks, and demodectic and sarcoptic mange. Simparica can also be used to treat ear mite infestations. For routine parasite control, both are given at monthly intervals. When using them to treat mite infestations, consult your veterinarian for advice, as further examination, testing, and possibly treatment, may be required.
At a Glance
- Prescription veterinary medicine in the form of a chewable, palatable tablet that is administered monthly
- Used in the treatment of both flea and tick infestations, and can form part of the management of flea allergic dermatitis
- Kills adult fleas within 8 hours of exposure to the product, and ticks within 48 hours of exposure
- Also used to treat demodicosis and sarcoptic mange
- Prescription veterinary medicine in the form of a chewable, palatable tablet that is administered monthly
- Used in the treatment of both flea and tick infestations, and can form part of the management of flea allergic dermatitis
- Kills adult fleas within 8 hours of exposure and ticks within 12 hours of exposure
- Ticks that are present on the dog before Simparica is administered are killed within 24 hours
- Used to treat demodicosis and sarcoptic mange
- In addition, can be used in the treatment of ear mite infestations
Overview of NexGard
- Easy to administer as a chewable, palatable tablet, or can be given with food
- Fast-acting, killing adult fleas within 8 hours and ticks within 48 hours of exposure
- Fleas are killed before they produce eggs, thereby helping break the cycle of reinfestation
- Adverse reactions have been reported very rarely (less than 1 in 10,000 animals), and when present have tended to be self-limiting and transient
- Treatment of fleas, ticks, demodicosis, and sarcoptic mange in one product
- Transmission of infectious parasite-borne diseases is still possible
- No safety data on use during lactation and pregnancy, or in breeding dogs so better to use an alternative product in these animals
- Potential for adverse reactions including gut upsets, itchiness, lethargy, loss of appetite, convulsions, wobbly gait, and muscle tremors
- Puppies need to be a minimum of 8 weeks old to receive the drug, and the minimum weight requirement is 2 kg, so may not be suitable for smaller breed puppies or very small dogs
Overview of Simparica
- Easy to administer as a chewable, palatable tablet, or given with food
- Fast-acting, killing adult fleas within 8 hours of exposure, newly attached ticks within 12 hours, and already attached ticks within 24 hours
- Fleas are killed before they produce eggs, thereby helping break the cycle of reinfestation
- Adverse reactions have been reported very rarely (less than 1 in 10,000 animals), and when present have tended to be self-limiting and of short duration
- Treatment of fleas, ticks, demodicosis, and sarcoptic mange in one product
- Also treats ear mite infestations
- Well tolerated in Collies, who are known to be more sensitive to drugs due to their genetic make-up
- Both flea and tick activity lasts for 5 weeks so there is some leeway if the interval between doses is longer than the recommended month
- The minimum weight requirement is 1.3 kg, so may be more useful in smaller breed puppies and dogs
- Not suitable for puppies under 8 weeks of age
- Transmission of infectious parasite-borne diseases is still possible
- No safety data on use during lactation and pregnancy, or in breeding dogs so better to use an alternative product in these animals
- Potential for adverse reactions including gut upsets, loss of appetite, lethargy, convulsions, wobbly gait, and muscle tremors
What are the differences between NexGard and Simparica?
While they share a lot of similarities, NexGard and Simparica have some notable differences. In addition to having activity against fleas, ticks, Demodex, and Sarcoptes, Simparica has a slightly broader spectrum of activity than NexGard as it can also be used to treat ear mites. While both products maintain efficacy against fleas for 5 weeks after administration, Simparica also kills ticks for 5 weeks, versus 4 weeks with NexGard. Both products kill fleas within 8 hours of attaching and feeding on the dog. Simparica has a slightly quicker onset of action in ticks, killing them within 12 hours of attaching and feeding, versus 48 hours in NexGard.
Both products can be used in puppies aged 8 weeks and older, but Simparica has a minimum weight requirement of 1.3 kg so may be more useful in treating smaller breed puppies and in very small dogs as NexGard requires a minimum weight of 2 kg. Simparica has also been tested in Collies, who have a known genetic predisposition to be more sensitive to some drugs and was found to be well tolerated.
In safety studies, some transient and self-limiting adverse effects have been observed in puppies treated with more than the maximum recommended dose of Simparica, while no adverse reactions were observed in puppies given above the maximum recommended dose of NexGard. It should be noted though that different testing protocols were in place for each drug, and none of these adverse effects were seen when Simparica was given within the recommended dose range.
What do the users say?
Both NexGard and Simparica received mosty very positive reviews on some online veterinary pharmacies. Most pet parents appeared very satisfied with the products. In some online pet forums, there was more of a mixed reaction. There was the occasional negative comment about safety, usually second-hand and anecdotal, but in the main consumers were highly satisfied with both NexGard and Simparica. The consensus appears to be that both products are very effective, safe, and pet parents would very happily continue to use them.
Conclusion
Both NexGard and Simparica fare equally as routine parasitic treatments. In the case of concurrent ear mite infestation, Simparica is the drug of choice. Both are very easy to give, being chewable tablets, and if that doesn’t work, you could always hide them in a favorite food! Cost-wise both products are similar, and consumer satisfaction among dog parents is high. Your veterinarian will be happy to discuss the suitability of either product for your pet at his or her next check-up.
