One good look at the options for flea protection out there, and you would think the smallest dog in the world was 5 pounds. Those of us who own chihuahuas know that many of them can end up being very small, some as small as 2 pounds.
Very small chihuahuas are more vulnerable to fleas because when they do get them, each bite takes proportionately more blood. On the flip side, it’s easy to give a small dog more pesticide on their skin than their body can tolerate, so getting the right dose is essential.
Can You Just Use Less Flea Protection?
When you are using flea protection, you are essentially placing poison on or in your dog. That’s what a pesticide is, it’s a product that can kill life. Flea protection is carefully formulated so that fleas can’t withstand the poison, but a healthy dog the weight the product is designed for can.
When used properly within the correct weight range, this means that the dog remains healthy and flea free, but any flea on them dies.
Because of this, only a veterinarian who is familiar with how these products work and what the health outcome is for a dog should make any changes to a recommended dosage. Too much flea protection can result in poisoning your dog. Too little can result in the flea protection not working.
Below are the flea protection options available. Most of these are prescription due to the limited options for small dogs, but there is one over the counter option for dogs less than 5 pounds.
Under Two Pounds
The world’s smallest chihuahua is just over a pound. If you have a similarly tiny pup, your only option is to have your vet modify an existing flea program to help your pet. Even prescription flea medication does not go this low and needs to be handled personally by a veterinarian.
Options for 2.8 Pounds and Up
Happily, the majority of very, very small dogs are over 3 pounds. If your dog is 2.8 pounds or above in weight, the best flea prevention is Simparica. Simparica is available for dogs as small as 2.8 pounds, and their Simparica Trio also does heartworms and regular worms as well as flea prevention.
It’s already a very good form of flea prevention and is safely rated for very small dogs. This is a prescription flea medication, so you will have to take your dog to the veterinarian if you want to use this treatment option.
Options for 4 pounds and up
More options become available the larger the size of the dog. Even though a 4-pound dog is still under the more common 5 pound limit on flea protection, a number of flea medications are available for dogs that are over 4 pounds.
These include NexGard and Revolution, which both have tiny dog options. NexGard is a chewable, and Revolution is a topical application for those who are more comfortable with this approach. (Let’s face it, it’s easier to squeeze something on a dog than convince them to eat a non-human-food treat.)
Over the Counter Options
Unfortunately, most over-the-counter options are 5 pounds and up. If your dog is under 3 pounds, you’ll almost certainly need to get a prescription flea prevention for your dog. There is one reputable option for flea protection over the counter that we are aware of, for dogs 3 pounds and over.
This is Advantage II. Advantage II is for dogs 3-10 pounds, making it a safe option for smaller chihuahuas, and also great if you have multiple chihuahuas in a range of weights.
The other major company, Frontline, does not have any options for dogs under 5 pounds.
What Happens If You Give Your Dog the Wrong Dose?
It’s easy to accidentally overdose flea protection on your pet. You may still see fleas after putting flea protection on your pet, and reapply early. You may try to put a 5 pound dose on a 2 pound dog. Giving your dog too much flea protection can lead to an overdose. Overdoses can occur both with chewables and topical applications. Symptoms can include:
- Excessive drooling
- Vomiting
- Tremors
- Itchy skin
- Seizures
- Weakness
- Difficulty breathing
If you see any of these symptoms in your dog after an overdose of flea treatment, call the pet poison hotline immediately. The pet poison hotline is 800-213-6680. There is a fee for the call, but it could save your pet.
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Tiny chihuahuas can be so vulnerable to fleas, and this post helps a lot. It’s comforting to know there are protections tailored for tiny pups under five pounds.