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The active substance of Bravecto™ is (13.7%) fluralaner, a synthetic ectoparasiticide (antiparasitic drugs used to kill the parasites that live on the body surface) which is a neonicotinoid: neuro-active insecticides chemically similar to nicotine. These chemicals act as a neurotoxin and interfere with the transmission of nerve impulses in insects.
Fluralaner is among the new classification of carbamoyl benzamide phenyl isoxazoline (CBPI: or simply isoxazoline[16]) insecticides that kill by binding to specific ligand-gated chloride channels (GABA-receptor and glutamate-receptors), causing paralysis and death.
Fluralaner is a systemically active treatment that circulates in the bloodstream: like fipronil and other (example: spot-on) neonicotinoids, fleas and ticks must attach to the dog and commence feeding in order to be exposed to the “active ingredient.”
The onset of effect is within 8 hours of attachment for fleas (C. felis) and 12 hours of attachment for ticks (Ixodes ricinus, Dermacentor reticulatus, D. variabilis and [US] ixodes scapularis).
Consumers may mis-anticipate certain results: because fleas and ticks must start feeding on the dog (ingest sufficient blood) in order to be killed by the insecticide, the risk of transmission of diseases with which they may be infected cannot be excluded... whether killing is fast enough to prevent disease transmission is not yet known.
Merck asserts that Braveco™—available in five different weight applications through veterinary prescription—can be used as part of a treatment strategy for the control of Flea Allergy Dermatits (FAD: as a direct result of eliminating intermittent exposure to flea saliva which initiates flea infestations).
Aussie-mix "Harley" on Jennings Beach in Fairfield, CT Harley: surfside sportsman... The proportion of inactive ingredients in Bravecto™ (see discussion above) is not disclosed on both US and non-US packaging, and listed as “secret” in Australian data sheets. This is “proprietary information” and only “hazardous” ingredients over 1% and/or “carcinogenic” ingredients in concentrations above .01% are listed in the chemical composition table. Merck’s US Material Data Safety Sheet captions only “CPBI, “starch,” [quotes added] polyethylene glycol, sucrose, and gylcerine,” with total product proportions that vary from 54.64% to 74.64%.[17] Detailed information on the toxicity and the fate of fluralaner in the dog's body (absorption, distribution, metabolism, excretion) and in the environment is sparse —(“The toxicological properties of the mixture(s) have not been fully characterized in humans or animals.”)—but users must contemplate that since it attaches to the protein in plasma and is slowly released and distributed to fatty tissues (where it kills insects), it would concentrate in kidney, liver, and muscle tissues: as the dog’s metabolic and renal systems recognize it as a toxin, and attempt to cleanse and repair the blood.[18]
Also notable was that no study was undertaken regarding the potential for “chronic/long term effects” (more than 168 days) of fluralaner (as Bravecto™) severally, or concerning the inactive ingredients as they might synergize and/or amplify it or each other. The Merck document discusses that the liver, as “the main elimination organ of CBPI” would likely be the main target of injury, but that a 90-day repeat-dose toxicity study (on rats) did not indicate damage, and as such, any degenerative changes “are considered to represent reversible metabolic effects and hence are of non-adverse character.” The liver is the singular organ in the body capable of regeneration.
Consumer advocacy groups monitoring the issue have been sharply critical that the trial done for Bravecto™, like Merial’s for Nexgard® (afoxolaner) was conducted/sponsored by Merck employees.
And as they would have anticipated, less than two years later the FDA’s Center for Veterinary Medicine (CVM) had registered more than 5,300 complaints of adverse reactions to Bravecto™; more than half of which were submitted for a six month period through early January 2016.
Similar to other neonicotinoids: sickness extended across gastrointestinal, neurological, endocrine, and renal turmoil to multi-organ toxicity/failure, blindness, euthanasia and death. Reports also include description of broad behavioral changes: particularly irritability and defensive (possibly fear-induced based on hallucinations) may accompany as the toxin accumulates in the adrenal and thryroid glands and the central nervous system.
Observers caution that the CVM database is likely incomplete: see discussion below. Some reports describe reactions several months into treatment... according to Merck’s Margin of Safety Study, “Dogs achieved steady-state fluralaner concentrations by the third treatment period.”
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Source: http://fairfieldbeachaccess.org/fleasandticks/controversyandconcern.html
Nog steeds Bravecto ?? 
Ik heb enkel de reacties gelezen van de mensen hier die het hebben gebruikt en wat ze hebben vastgesteld. 
Jammer dat Klazien uut Zalk er niet meer is anders zou ik haar bellen ;-)
