Simparica is an FDA and APVMA-approved flea and tick control product that is recommended for monthly use and is considered safe to use in dogs. More than 200 million doses have been distributed globally, protecting pets all over the world.
The active ingredient Sarolaner is a member of the isoxazoline class, which is the same class of medication used in other flea control products such as NexGard and Bravecto. All isoxazoline medications control fleas and other parasites through effects on the parasite’s nervous system. Side effects to the isoxazoline family of parasiticides are rare and are most likely to include vomiting, diarrhoea and lethargy. On very rare occasions, seizures have been observed. Most reactions to the isooxazoline class are self-limiting and of short duration. Vetwest uses and recommends isooxazoline products for flea control because we believe they are safe and effective and provide a significant health benefit to our patients. If you have any concerns, please contact us or contact the product support number provided by the manufacturer on the packaging.

You can find out more on the Zoetis website