NexGard starts killing fleas within 4 hours and eliminates 100% of fleas within 24 hours.
NexGard is a beef-flavored chewable tablet containing afoxolaner, which targets the nervous system of fleas and ticks. After administration, the active ingredient rapidly enters the bloodstream, killing adult fleas before they can lay eggs. The product remains effective for 30 days, providing continuous protection against reinfestation.
How NexGard works to eliminate fleas
- Afoxolaner disrupts flea nervous systems by blocking GABA and glutamate receptors
- Flea death occurs through hyperactivity and paralysis within hours
- Protection lasts 30 days with monthly dosing
- Works on both adult fleas and ticks
Comparison of flea treatment onset times
| Treatment | Starts killing fleas | Complete elimination | Duration |
|---|---|---|---|
| NexGard | 4 hours | 24 hours | 30 days |
| Frontline Plus | 12 hours | 18 hours | 30 days |
| Advantage II | 12 hours | 24 hours | 30 days |
Factors affecting flea elimination speed
- Infestation severity: Heavy infestations may take longer to clear
- Dog's weight: Proper dosing based on weight ensures optimal effectiveness
- Environmental control: Treating bedding and surroundings prevents reinfestation
- Concurrent treatments: Using multiple products may interfere with efficacy
Safety and administration guidelines
- Administer with or without food
- Give whole chewable tablet, not broken pieces
- Monthly dosing maintains continuous protection
- Safe for puppies 8 weeks and older weighing 4+ pounds
Monitoring effectiveness
Check your dog 24 hours after first dose for dead fleas. Continue monthly treatments even if fleas aren't visible, as new fleas can jump onto your pet from the environment. If live fleas persist after 48 hours, consult your veterinarian about potential resistance or improper administration.