March 26, 2018
I kill fleas on your dog for up to 3 months.
What molecule am I?

Spring is finally here. Tennyson wrote, “In the Spring a young man’s fancy lightly turns to thoughts of love,” but these days, a pet owner’s fancy often turns to thoughts of controlling fleas on his or her furry friends.

Many treatments are in use to repel fleas (and ticks) from dogs and cats or to kill the insects once an infestation occurs: Treatments include topical powders and liquids, flea collars, and oral medications. All of these methods have advantages and disadvantages; the Internet is full of arguments for and against each.

In 2014, the US Food and Drug Administration approved the use of fluralaner (trade name Bravecto), a chewable tablet for dogs that is administered at 12-week intervals. This is a significant improvement to oral products that must be taken monthly. Fluralaner is a systemic insecticide that inhibits GABA-gated and l-glutamate-gated chloride channels in the insects’ nervous system.

FDA evidently considered the compounded product Bravecto to be safe enough for general use, but a glance at the hazard information box reveals that fluralaner itself is not to be handled carelessly. The dosage of fluralaner in Bravecto ranges from 112.5 mg to 1.4 g, depending on the weight of the dog to be treated. It can be inferred that even at the highest dose, Bravecto is deemed safe to be handled by the dog’s human companion.


Fluralaner fast facts

CAS Reg. No. 864731-61-3
Molar mass 556.29 g/mol 
Empirical formula C22H17Cl2F6N3O3
Appearance White to off-white crystals or powder
Melting point Not available
Water solubility Insoluble

Fluralaner hazard information

GHS classification*: skin irritation, category 2
H315—Causes skin irritation  Chemical Safety Warning
GHS classification: skin sensitization, category 1
H317—May cause an allergic skin reaction Chemical Safety Warning
GHS classification: serious eye damage, category 1
H318— Causes serious eye damage Chemical Safety Warning
GHS classification: respiratory sensitization, category 1
H334—May cause allergy or asthma symptoms or breathing difficulties if inhaled Chemical Safety Warning
GHS classification: specific target organ toxicity, single exposure; respiratory tract irritation, category 3
H335—May cause respiratory irritation Chemical Safety Warning
GHS classification: germ cell mutagenicity, category 2
H341—Suspected of causing genetic defects Chemical Safety Warning
GHS classification: reproductive toxicity, category 2
H361—Suspected of damaging fertility or the unborn child. Chemical Safety Warning
GHS classification: specific target organ toxicity—single exposure, category 1
H371—May cause damage to organs Chemical Safety Warning
GHS classification: Hazardous to the aquatic environment, long-term hazard, category 4
H413—May cause long-lasting harmful effects to aquatic life Chemical Safety Warning

*Globally Harmonized System of Classification and Labeling of Chemicals. Explanation of pictograms.

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