What happens to fleas after drops are applied to the neck? - briefly
Topical antiparasitic drops applied to the neck penetrate the flea’s exoskeleton, causing rapid paralysis and death; the insects then detach and fall from the host.
What happens to fleas after drops are applied to the neck? - in detail
When a liquid insecticide is placed on the animal’s neck, the substance spreads across the skin and hair shaft through capillary action. The active ingredients penetrate the exoskeleton of any flea present, disrupting its nervous system and causing rapid paralysis. Within seconds to a few minutes, immobilized fleas lose the ability to jump or feed.
The process continues as follows:
- Absorption: The formulation is designed to be absorbed into the sebaceous glands, creating a reservoir that releases medication over weeks.
- Contact toxicity: Fleas that land on the treated area encounter the chemical on the fur, leading to immediate knock‑down.
- Systemic effect: Some products are absorbed into the bloodstream; feeding fleas ingest the toxin when they bite, resulting in internal poisoning and death.
- Environmental spread: As the animal moves, the treated hair contacts other parts of the body, extending the protective zone and killing fleas that crawl elsewhere.
- Lifecycle interruption: By eliminating adult fleas and preventing egg production, the treatment breaks the reproductive cycle, reducing future infestations.
The net result is a swift decline in flea activity on the host, followed by a sustained reduction in the population as the medication persists on the skin and in the animal’s system.