I was just curious as to what makes a drug a systemic repellent as opposed to the Bravecto "where they bite first". Curious about their mechanism of action. Our insect repellents work by sitting on our skin, a midge or something then either touches it or inhales molecules of the chemical from our skin to work. I think DEET paralyses the "landing and biting gear" of mosquitos. Just did a quick google So I guess the chemicals are also constantly being distributed around dog beds, houses, floors, clothing, hands etc....... I am guessing after the initial application period where the wildlife/waterway issue is known, that it is then ok?
This is an explanation of how Advantix works: Advantix Spot-on is an ectoparasiticide for topical use containing imidacloprid and permethrin . This combination acts as an insecticide, acaricide and as a repellent. Imidacloprid is an ectoparasiticide belonging to the chloronicotinyl group of compounds. Chemically, it can be classified as a chloronicotinyl nitroguanidine. Imidacloprid is effective against adult fleas and larval flea stages. In addition to the adulticide flea efficacy of imidacloprid, a larvicidal flea efficacy in the surroundings of the treated pet has been demonstrated. Larval stages in the dog's immediate surroundings are killed following contact with a treated animal. It has a high affinity for the nicotinergic acetylcholine receptors in the post-synaptic region of the central nervous system (CNS) in insects. The ensuing inhibition of cholinergic transmission in insects results in paralysis and death of the parasite. Permethrin belongs to the type I class of pyrethroid acaricides and insecticides and also acts as repellent. Pyrethroids affect the voltage-gated sodium channels in vertebrates and non-vertebrates. Pyrethroids are so called “open channel blockers” affecting the sodium channel by slowing both the activation and the inactivation properties thus leading to hyperexcitability and death of the parasite. In the combination of both substances, it has been shown imidacloprid functions as the activator of arthropod ganglia and therefore increases the efficacy of permethrin. The product provides repellent (anti-feeding) activity against ticks, sand flies and mosquitoes, preventing the repelled parasites from taking a blood meal and thus reducing the risk of disease transmission (e.g. borreliosis, rickettsiosis, ehrlichiosis, leishmaniasis). However, there may be an attachment of single ticks or bites by single sand flies or mosquitoes. For this reason, a transmission of infectious diseases by these parasites cannot be completely excluded if conditions are unfavourable. The product provides repellent (anti-feeding) activity against stable flies thereby assisting in the prevention of fly-bite dermatitis. The product is indicated for dermal administration. Following topical application in dogs, the solution rapidly distributes over the body surface of the animal. Both active substances remain detectable on the skin and hair of the treated animal for 4 weeks. Acute dermal studies in the rat and target animal, overdose and serum kinetic studies have established that systemic absorption of both active substances after application on intact skin is low, transient and not relevant for the clinical efficacy.
I wonder how it does that? Wonder if it also "migrates" vial the skin oil glands like the Frontline. Not entirely sure I understand how it works. (OK guys, sorry, I am too much of a "reflector", need to understand it) I can't think of anything equivalent in human meds and I think that is the problem........ How long does it take to migrate? (a rhetorical question, not expecting an answer Julie, just musing.....) If you put it on the neck, how long does it take to get to the leg to act as a repellant as opposed to just relying on the "blood meal" approach of attack?
We looked it up for advocate when we had a discussion about why advocate doesn't wear off when the dog swims - from memory - it was absorbed into the top layer of subcutaneous fat under the skin. But my knowledge of biology stops there....
