Safe use of flea and tick preventive products

They're creepy, they're crawly...and they can carry diseases. Fleas and ticks are not just a nuisance, but pose animal and human health risks. They suck your pet's blood, they suck human blood, and can transmit diseases.  Some of the diseases that fleas and ticks can transmit from animals to humans (zoonotic diseases) include plague, Lyme disease, Rocky Mountain Spotted Fever, bartonellosis and others.  That's why it's critical to protect your pets from these pesky parasites and keep the creepy crawlies out of your home.   

Fortunately, there are many effective flea and tick preventives on the market to help control the pests and prevent the spread of zoonotic diseases. Knowing what kind of product to use, and how to use it, is critical to the health and safety of your pet. Many are spot-on (topical) products that are applied directly to your pet’s skin, but there are some that are given orally (by mouth). Although medicines and pesticides must meet U.S. government-required safety standards before they can be sold, it is still critical that pet owners carefully consider their flea and tick preventive options (and closely read the label) before they treat their pets with one of these products.

Ask your veterinarian

Consult your veterinarian about your options and what’s best for your pet. Some questions you can ask include:

  • What parasites does this product protect against?
  • How often should I use/apply the product?
  • How long will it take for the product to work?
  • If I see a flea or tick, does that mean it's not working?
  • What should I do if my pet has a reaction to the product?
  • Is there a need for more than one product? 
  • How would I apply or use multiple products on my pet?

Parasite protection is not “one-size-fits-all.” Certain factors affect the type and dose of the product that can be used, including the age, species, breed, life style and health status of your pet, as well as any medications your pet is receiving.  Caution is advised when considering flea/tick treatment of very young and very old pets. Use a flea comb on puppies and kittens that are too young for flea/tick products. Some products should not be used on very old pets.  Some breeds are sensitive to certain ingredients that can make them extremely ill. Flea and tick preventives and some medications can interfere with each other, resulting in unwanted side effects, toxicities, or even ineffective doses; it’s important that your veterinarian is aware of all of your pet’s medications when considering the optimal flea and tick preventive for your pet. 

How to protect your pets

To keep your pets safe, we recommend the following:

  • Discuss the use of preventive products, including over-the-counter products, with your veterinarian to determine the safest and most effective choice for each pet.
  • Always talk to your veterinarian before applying any spot-on products, especially if your dog or cat is very young, old, pregnant, nursing, or on any medications.
  • Only purchase EPA-registered pesticides or FDA-approved medicines.  
  • Read the entire label before you use/apply the product.
  • Always follow label directions! Apply or give the product as and when directed. Never apply more or less than the recommended dose.
  • Cats are not small dogs. Products labeled for use only for dogs should only be used for dogs, and never for cats. Never.
  • Make sure that the weight range listed on the label is correct for your pet because weight matters.  Giving a smaller dog a dose designed for a larger dog could harm the pet.


One pet may react differently to a product than another pet. When using these products, monitor your pet for any signs of an adverse reaction, including anxiousness, excessive itching or scratching, skin redness or swelling, vomiting, or any abnormal behavior. If you see any of these signs, contact your veterinarian. And most importantly, report these incidents to your veterinarian and the manufacturer of the product so adverse event reports can be filed.

Be aware that certain flea and tick preventives are regulated by the Environmental Protection Agency (EPA), while others are regulated by the Food and Drug Administration (FDA).  It can seem confusing at first to figure out which agency regulates the product you’re using, but it’s actually pretty straightforward: if the product is regulated by the EPA, there’s an EPA number clearly listed on the package. If it’s regulated by the FDA, there should be a NADA or ANADA number clearly listed on the package. Check the label for either an EPA or an FDA approval statement and number.  If you see neither, check with your veterinarian before purchasing and especially before using the product.

For more information:

Animal Tracks Podcast: Ticks and our pets  
Animal Tracks Podcast: My dog (or cat) has fleas?