How do flea and worm drops for cats work when applied to the neck? - briefly
Applied to the nape, the liquid spreads across the skin, is absorbed into the bloodstream, and circulates systemically to eliminate fleas and intestinal worms. The active insecticide or anthelmintic compounds target the parasites’ nervous or metabolic systems, delivering rapid, lasting protection.
How do flea and worm drops for cats work when applied to the neck? - in detail
Topical ectoparasitic and endoparasitic solutions for felines are administered as a single dose of liquid placed on the skin at the base of the skull. The thin skin in this area allows rapid penetration of the active compound into the dermal capillaries. Once in the bloodstream, the molecule is carried throughout the body, reaching the skin surface, hair follicles, and internal organs where parasites reside.
The flea‑killing component, usually a neurotoxin such as imidacloprid or fipronil, binds to insect‑specific ligand‑gated ion channels. After systemic distribution, it accumulates in the sebum and on the coat, where feeding fleas ingest a lethal dose. The worm‑targeting ingredient, often a macrocyclic lactone like milbemycin oxime, interferes with glutamate‑gated chloride channels of nematodes. Systemic circulation delivers the drug to the gastrointestinal tract and tissues, where it paralyzes and eliminates intestinal and tissue‑dwelling worms.
Key steps in the process:
- Application: A calibrated drop is placed on the shaved spot behind the ears; the cat’s grooming behavior spreads the liquid across the neck and head.
- Absorption: Lipophilic formulation penetrates the epidermis within minutes, entering capillary vessels.
- Distribution: Plasma transport carries the agents to peripheral skin, hair shafts, and internal organs.
- Target interaction: Flea neurotoxin disrupts insect nerve transmission; macrocyclic lactone blocks nematode muscle contraction.
- Elimination: Metabolic pathways in the liver convert the compounds to inactive metabolites, which are excreted via feces and urine.
Efficacy depends on correct dosing relative to the cat’s weight, proper placement to avoid dilution by excessive licking, and adherence to the product’s interval schedule. Systemic action ensures protection against both external and internal parasites from a single application site.