Hi stranger! Signing up for MypetMD is easy, free and puts the most relevant content at your fingertips.

Get Instant Access To

  • 24/7 alerts for pet-related recalls

  • Your own library of articles, blogs, and favorite pet names

  • Tools designed to keep your pets happy and healthy

or Connect with Facebook

By joining petMD, you agree to the Privacy Policy.

Killing Fleas! How Long Do Flea and Tick Medications Take to Work?

By Jennifer Coates, DVM


When you find fleas and ticks on your pet, you want them gone immediately. But with so many treatments available, how do you know which one will work fast?


Some flea and tick medications take quite a long time to become effective, but others can bring your dog or cat relief within just a couple of hours! Information about how quickly a medication starts to work is easily available by reading the product label, visiting the manufacturer’s website, or by talking to your veterinarian.


Another important consideration is how the flea and tick medication is applied. Shampoos, dips, collars, spot-ons, pills, and chewable tablets are all available and can be used to good effect.


Make the right choice for you based on your particular situation. For example, owners with children sometimes prefer a flea and tick pill or chewable tablet over a topical preparation to limit the chances that their kids will inadvertently come in contact with medicine on their pet’s skin.


Choosing a flea and tick medication that works quickly and comes in the right formulation for you is only part of the battle, however.


Because fleas and ticks live on dogs and cats for only a small part of their life cycle, most of these parasites are found in the environment at any given time. As these young fleas and ticks mature, they eventually will seek out your pet, causing a new infestation.


The presence of fleas and ticks in a pet’s environment make two additional aspects of parasite control critical:


1. The Length of Time Flea and Tick Medications Last


Flea and tick treatments that remain active for only a few hours or days are not practical for most dog and cat owners. Who has the time to be re-treating their pets so frequently?


The development of products that last for several weeks was a huge step forward, and now some newer flea and tick treatments last for even longer — up to several months with only one dose! Using a long-acting flea and tick medication decreases the risk associated with missed doses.


2. Environmental Control of Fleas and Ticks


Many medications are effective at quickly killing fleas and ticks that are on pets, but owners still have to deal with the parasites that are in the house or yard. Environmental control is vital and often overlooked.


Flea eggs and larvae in the house are best removed by vacuuming floors, carpets, and furniture (pay special attention to out of the way areas and crevices), and by running pet bedding and anything else that is washable through the washer and dryer’s hottest cycles.


The numbers of fleas and ticks outdoors can be greatly reduced through the use of a yard and premise spray.


All dogs and cats in the house need to be on effective flea and tick medications to completely get rid of an infestation, but treatments that are only labeled for use on dogs should never be given to cats.


Before giving your cat any type of medicine, confirm that it is safe by closely reading and following the instructions on the product label. If you have any questions or concerns about the use of flea and tick medications for your cats or dogs, talk to your veterinarian.


Image: bikeriderlondon / via Shutterstock

Around the Web