How Old Should a Puppy Be to Put on a Flea Collar?

Young puppies need safe, effective flea control.
i Jupiterimages/Comstock/Getty Images

Fleas can be a pain, both for your new puppy and everyone else in your household. If your new pup is younger than 4 to 6 weeks old, though, you might want to hold off on a flea collar entirely and look into other methods of keeping your pooch flea-free.


Pyriproxifen, which stops the flea growth cycle and kills young fleas, is a common ingredient in flea collars, and it is also used in topical products designed to be applied to the back of your dog's neck. It is not safe for puppies younger than 7 weeks old. Ingredients such as pyrethrum, limonene and linalool may be fine for puppies older than 4 to 6 weeks, but you should consult your vet before exposing your puppy to these insecticides.


Puppies are more susceptible to the insect-killing ingredients in flea collars because they are smaller than full-grown dogs and have less-developed immune systems. Puppies also are more likely to chew on a flea collar if it becomes loose, increasing the risk of ingesting the toxic compounds. In addition to the potential toxicity of flea collar ingredients, another concern is choking. Some flea collars are too loose for a puppy's small neck, so they can become caught on household furniture and accidentally choke your poor guy.


If your puppy is too young to use a flea collar, or if you prefer to try a different method of flea control, flea dips or shampoos can be an effective option. Flea combs can remove adult fleas, but they will not remove flea eggs, so you will have to repeat the combing procedure frequently. House flea treatments, such as carpet sprays and flea bombs, may be necessary if your home is heavily infested. If your puppy is older than 6 weeks, your vet may recommend a topical solution or oral medication to eliminate fleas. These products tend to be more effective than flea collars because they treat the entire pet, not just the area around the head and neck.


Don't avoid treating fleas just because you are concerned about the toxicity of flea collars. Fleas not only make your pet uncomfortable, they can also carry dangerous diseases, such as heartworms. Some dogs and puppies develop allergies to fleas, which can result in skin redness, skin irritation and hair loss. Young puppies may become anemic from the severe blood loss that accompanies a severe flea infestation.

Always check with your veterinarian before changing your pet’s diet, medication, or physical activity routines. This information is not a substitute for a vet’s opinion.

the nest