NexGard and Frontline Plus both work. The differences come down to how they work, what they cost, and what your dog's life looks like day-to-day.
How they work
NexGard is an oral chewable given once a month. The active ingredient is afoxolaner, which enters your dog's bloodstream and kills fleas and ticks when they bite. Because it's systemic, bathing and swimming don't affect it at all.
Frontline Plus is a topical applied to the skin at the back of the neck, also monthly. It contains fipronil and (S)-methoprene, which spread through the skin's oil layer and kill fleas and ticks on contact. It's waterproof after about 24 hours, but you need to wait that window before getting your dog wet.
Effectiveness
Both are effective when used consistently. NexGard kills fleas within 4 hours and ticks within 24–48 hours. Frontline Plus takes a bit longer — fleas within 12 hours, ticks within 48. Neither product repels insects; they kill after contact or bite.
For dogs that swim constantly or get bathed often, NexGard has a clear practical edge. For everyone else, the difference in kill speed is unlikely to matter much.
Prescription and access
NexGard requires a prescription. Frontline Plus doesn't — it's sold over the counter at most pet retailers and online. That affects where you can buy and how much friction is involved in getting it.
Cost comparison
| Product | Per dose (medium dog) | 6-month supply | |---|---|---| | NexGard | $20–$28 | $58–$85 | | Frontline Plus | $12–$18 | $45–$65 | | Generic afoxolaner | $14–$20 | $40–$58 |
NexGard's active ingredient now has FDA-approved generics that cost meaningfully less than the brand. Frontline Plus has generic entrants too — products with the same fipronil and (S)-methoprene formulation at lower prices. Check PetSaver for current pricing across retailers before you commit to either.
Which to pick
If your dog swims a lot, dislikes topical treatments, or you just want the simplicity of a chew, NexGard (or its generic) is the better fit. If cost is the main factor or your dog won't take oral medications, Frontline Plus makes sense. Your vet may also have a preference based on your area's tick species — some ticks respond better to one mechanism than the other.
Whatever you land on, prices vary by 30–40% across retailers for the same product. Worth a quick comparison before you check out.