What Are the Treatments for Flea Medicine Toxicity in Dogs?

Most symptoms of flea medication poisoning resolve with a few days.
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Fleas are annoying at best and painful at worst for dogs. Conscientious dog parents take steps to keep the tiny bloodsuckers at bay. But if your solution for treating fleas involves powders, sprays or collars, you must be aware of the risks these chemicals pose to canines. Flea medicine poisoning can ultimately do more harm than fleas themselves.

Dangerous Ingredients

Most commercial flea products are safe if used according to instructions, though you must take care when applying topical flea treatments or collars. Most collars contain chemicals such as tetrachlorvinphos and propoxur, which release flea-repelling medicines into the fur. Topical sprays and powders often contain pyrethrins, which are derived from chrysanthemums, or their synthetic cousins, pyrethroids. The danger comes less from leeching chemicals on fur than from licking or biting irritated areas where flea medicines rest, or inhaling powder.

Symptoms of Poisoning

Poisoning from powders and sprays used to treat a flea infestation is more common than poisoning from collars. A dog's reaction to pyrethrins or pyrethroids can range from mild to moderate allergies or hives to nausea, respiratory distress and tremors to vomiting and shock. Excessive drooling, agitation and excitability are also common signs of flea medication poisoning. In more severe cases, tremors can lead to seizures. If you see any of these symptoms, call your vet at once.


Typically, dogs reacting to a flea treatment will flick their ears or scratch, though these reactions are usually mild and don't last long. However, these early symptoms suggest that your dog may be too saturated with chemicals. Use a dry towel to soak up the excess. If symptoms persist, wash her in a warm bath with mild soap, such as liquid dish detergent, to get the chemicals off her fur.

Worse Symptoms

If ear flicking or scratching graduates to shaking, incoordination or salivation, get your dog to a vet or animal hospital immediately. Do not try to wash him if these symptoms appear. At this point, the poison may be in his system and he will need to be stabilized and likely given fluids. After he is stabilized, wash him in liquid soap and warm water. Warm water is critical in order to prevent shock. Your vet may also prescribe medicine to help detoxify his system.