
How to Apply Flea Treatment: Where, When, and Why
Looking for different types of flea treatment for your dog or cat? There’s a lot to consider when it comes to flea control.
If you’ve narrowed your search to topicals you’ll want to know what to look for and when, where, and how to apply flea medicine. But the instructions for putting it on aren’t always straightforward. We can help.
What to look for in flea and tick protection
Form factor
There are a variety of methods for killing fleas on cats and dogs — including flea collars and oral flea products.
Brand
While vet-quality products are well-known across the country, you don't necessarily need name-brand products to get the job done.
Ingredients
The right solution can give your pet a competitive advantage against fleas and ticks. Certain ingredients help break the flea life cycle (i.e. flea eggs, larvae, and adult fleas).
How to apply flea treatment to dogs
The steps for how to apply topical flea treatment to dogs aren’t always the same. Before you begin applying, be sure to read through the instructions.
The amount of formula in spot-on flea treatment often aligns with your dog’s weight. If they’ve gained or lost weight since your last treatment, you may need a different dose. Confirm their weight still matches the range listed on the box.

Here are some helpful steps for how to apply flea and tick treatment for dogs.
- Remove the tube from the pack and locate your dog
- Hold the tube vertically and open the tip
- Follow the instructions to apply as directed
- Throw the applicator in the trash (never put unused treatment down any drain)
When
While minimum age and weight vary by product, new puppies should be at least 7-10 weeks old and 3-5 pounds before using a topical flea preventative. Make sure you check the package and your dog’s weight regularly to apply the right dose.
The best protection is regular use to protect your pup from fleas and ticks. This means that, with most topicals, you should be reapplying at least every 30-days.
There’s no right or wrong time of day to treat your pet. But, you shouldn’t wash or bathe your dog for at least 48 hours before or after applying. Doing so strips away the natural oils on your pet's skin help boost the effectiveness of the product. So, avoid contact with treated areas until dry.
Once treatment has dried, immediately resume playing and snuggling with your pet. Applying medication should be stress-free! Show your pet some love with extra hugs and treats before and after application.
Where
To ensure your dog keeps fleas and ticks at bay, you’ll want to apply the formula in the right spots. While every topical treatment is different there are a few things to keep in mind.

- Comb or part the hair near their neck and shoulder blades
- Ensure the treatment is applied directly to their skin, not their fur
- Keep your dog sitting or standing upright
EXPERT ADVICE
Some treatments require you to apply in several spots along your dog’s spine — starting at your pet's neck and ending at the base of their tail.
How to apply flea treatment to cats
Just like applying flea treatment to dogs, there are a few ways to properly apply topical flea treatment to your cats. As always, read through the provided instructions on your package. And, be sure to follow these tips for when and where you should treat your cat.

Every applicator tube is different. Start by reading through the instructions and follow these tips for how to apply topical flea treatment to cats:
- Ask another person for help holding your cat
- Remove the tube and hold it vertically when opening
- Empty the tube completely, then place it in the trash
- Don't let your cat lick or get the treatment in their eyes
When
Depending on the medication your cat may need to be a specific weight and age. This can vary from 1.5 to 5 pounds and 8 to 12 weeks. As kittens grow and age, you may need to adjust their dosage. Confirm their weight still matches the range listed on the box.
You may be wondering, how often can you apply flea medicine to cats? Just like dogs, you should only apply topical flea medicine once every 30 days.
As with dogs, your cat should be completely dry before treating. If you give them a flea bath prior, make sure you wait at least 48 hours before applying treatment. Then, keep your cat dry for at least 24 hours to ensure the liquid spreads evenly.
Where
If you have a multi-pet household, it's important to keep your treated cat separate from all other pets. Make sure your pets don't rub against each other or get into bedding or articles of clothing post-application.
VET TIP
Some topical cat flea treatments (meant for dogs) can be deadly for cats. Permethrin, a common chemical used in spot-on formulas, is highly toxic for cats.

Additionally, there are a few ways to ensure you are applying in the right spots.
- Part the hair near your cat's neck (base of the skull)
- Apply the treatment directly to their skin
- Keep your cat sitting or standing to ensure liquid doesn’t run off their side
Why topical flea treatment works
Spot-on flea treatment is great for a few reasons:
- Fleas and ticks don’t have to bite or feed on your pet to work. This ensures your pet avoids skin irritation and infection such as Flea Allergy Dermatitis (FAD).
- They contain active ingredients that are effective at killing and preventing fleas. This can also include fleas (all life cycle stages — adult fleas, flea eggs, and flea larvae) ticks, lice, and sometimes mosquitoes.
- They are generally more affordable than other preventatives. Plus, oral treatments require a prescription from a licensed veterinarian.
But, there are a few things to be aware of with topical flea products.
- No matter what type of treatment you choose, you should always get veterinary advice beforehand. A vet can speak to your pet’s unique needs and suggest the right treatments.
- Though extremely rare, your pet may experience a few side effects. These can be hard to detect because they are similar to the symptoms of flea and tick bites. Some include itching, lethargy, and digestive issues.
- Watch for any sign of irritation and be sure to contact your veterinarian and take your pet in if things worsen.
Let's face it — problems like fleas, ticks, and worms are the worst. Being a good pet parent means giving your pet the best advantage against harmful pests.
The best way to prevent fleas, and avoid flea infestation, is through monthly prevention. Contact our helpful team if you have any questions regarding flea and tick protection.