How does a tick medication tablet work on ticks in dogs? - briefly
The tablet delivers a systemic insecticide that circulates in the bloodstream, killing ticks that attach and feed. Rapid absorption ensures lethal concentrations are reached within hours, preventing attachment and reducing disease transmission.
How does a tick medication tablet work on ticks in dogs? - in detail
Tick‑control tablets for dogs deliver a systemic insecticide that circulates in the bloodstream after oral administration. The active compound, typically an isoxazoline such as afoxolaner, fluralaner, or sarolaner, is absorbed through the gastrointestinal tract within a few hours. Once in the plasma, it binds to plasma proteins and distributes to tissues, maintaining therapeutic concentrations for several weeks.
The insecticide targets ligand‑gated chloride channels in arthropod nervous systems. Specifically, it blocks GABA‑gated and glutamate‑gated channels, preventing inhibitory neurotransmission. This disruption leads to uncontrolled neuronal firing, paralysis, and death of the tick. Because the drug is present in the host’s blood, a feeding tick ingests a lethal dose during attachment and blood‑meal acquisition.
Key aspects of the mechanism include:
- Rapid absorption: Peak plasma levels reached within 2–4 hours after ingestion.
- Sustained exposure: Effective concentrations persist for 4–12 weeks, depending on the product.
- Systemic action: No external contact required; efficacy relies on the tick’s blood intake.
- Broad stage activity: Adult, nymph, and larval ticks are affected once they feed, interrupting the life cycle.
- Selective toxicity: Mammalian GABA receptors differ sufficiently to avoid significant adverse effects at therapeutic doses.
Pharmacokinetic parameters support the clinical effect. The half‑life ranges from 12 days (afoxolaner) to 12 weeks (fluralaner), allowing monthly or quarterly dosing intervals. Metabolism occurs primarily in the liver via cytochrome P450 enzymes, and elimination is mainly fecal.
Safety considerations involve:
- Dose accuracy: Administration based on body weight prevents under‑ or overdosing.
- Drug interactions: Concomitant use of strong CYP inducers may reduce plasma levels.
- Breed sensitivities: Certain breeds (e.g., Collies) may exhibit heightened sensitivity to some compounds; veterinary guidance is required.
Resistance monitoring is essential. Repeated exposure can select for tick populations with altered target sites, reducing efficacy. Rotating products with different active ingredients mitigates this risk.
In practice, a single tablet administered orally provides systemic protection that kills feeding ticks, prevents attachment of new parasites, and reduces the risk of tick‑borne diseases transmitted during blood feeding.