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This guide is general education for pet owners. If your pet has urgent symptoms, possible poisoning, injury, breathing trouble, collapse, severe pain, or sudden decline, contact a licensed veterinarian or local emergency service.
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NexGard (Afoxolaner) for Dogs: Monthly Flea/Tick Safety Triage
Clinical Classification & Indications
- Drug Class: Isoxazoline Class Ectoparasiticide
- Approved Uses: Monthly prevention and treatment of flea infestations and control of major tick vectors (blacklegged tick, American dog tick, Lone Star tick) in dogs.
Mechanism of Action (Pharmacodynamics)
Binds specifically to insect and acarine GABA and glutamate-gated chloride channels in nerve synapses, blocking chloride transfer and inducing spastic paralysis in parasites.
Adverse Reactions & Side Effect Profile
Common / Expected Side Effects
Vomiting, dry/flaky skin, diarrhea, lethargy, anorexia.
Emergency Red Flag Reactions
Acute onset of whole-body tremors, profound unsteadiness, or seizure activity post-chew ingestion.
Clinical Contraindications & Interactions
- Do Not Use In: Dogs with documented seizure disorders. Not approved for puppies younger than 8 weeks or weighing under 4 lbs.
Strict Rule S1 Veterinary Prescription Directive
VETERINARY DIRECTIVE: NexGard is formulated as a palatable beef-flavored soft chew. Because dogs find it delicious, store all boxes high in childproof/petproof cabinets—accidental ingestion of the entire multi-pack by a counter-surfing dog is a frequent cause of emergency clinic visits. Never administer human pharmaceutical products or adjust dosages without direct examination and bloodwork by a licensed Doctor of Veterinary Medicine (DVM).
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