How long does a tick injection administered to a dog remain effective?

How long does a tick injection administered to a dog remain effective? - briefly

A tick‑preventive injection for dogs typically provides protection for 8 to 12 weeks, depending on the specific product and its active ingredient. After this period the efficacy declines, and a new dose is required to maintain continuous protection.

How long does a tick injection administered to a dog remain effective? - in detail

Tick injections for canines contain systemic acaricides that circulate in the bloodstream and kill attached ticks. The period during which a single dose provides protection varies by active ingredient, formulation, and dosage relative to the animal’s weight.

Common products and their typical efficacy windows:

  • Fluralaner (Bravecto®) – 12 weeks of protection after a single injection.
  • Afoxolaner (NexGard®) – 4 weeks per dose; monthly administration required.
  • Sarolaner (Simparica®) – 4 weeks per dose; monthly administration required.
  • Lotilaner (Credelio®) – 4 weeks per dose; monthly administration required.
  • Isoxazoline‑based injectable formulations (e.g., Bravecto® Injectable) – 12 weeks of activity.

Factors influencing the duration of effectiveness:

  • Accurate dosing based on the dog’s current weight; under‑dosing shortens the protection period.
  • Health status, particularly liver and kidney function, which affect drug metabolism.
  • Seasonal tick pressure; high exposure may reveal reduced efficacy sooner.
  • Development of resistance in local tick populations; ongoing surveillance recommended.

Veterinary assessment determines the appropriate product, dosing schedule, and any necessary adjustments for individual animals. Regular re‑evaluation ensures continued protection throughout the tick season.