No, dogs should not be around mothballs. Mothballs are toxic to all species, including dogs, and the danger comes from both ingestion and prolonged exposure to the fumes. A single mothball contains enough chemical to make a dog seriously ill, and the sweet, waxy appearance can attract curious pets who mistake them for treats or toys.
What Makes Mothballs Dangerous
Mothballs are made from one of two chemicals: naphthalene or paradichlorobenzene. Naphthalene mothballs are the more common and more dangerous variety, containing 99.9% naphthalene. A third, less common type uses camphor. All three are toxic to dogs, but they cause harm in different ways.
Naphthalene damages red blood cells. When a dog ingests it, the chemical breaks down red blood cells faster than the body can replace them, leading to a type of anemia. It can also change the structure of hemoglobin (the protein that carries oxygen in the blood), reducing the blood’s ability to deliver oxygen to organs. In dogs, ingesting roughly 1.5 grams per kilogram of body weight can trigger this blood cell destruction. For a 20-pound dog, that could be as little as one or two mothballs depending on their size.
Paradichlorobenzene is generally less acutely toxic than naphthalene, but there is no established safe threshold for dogs. Even small amounts can cause neurological symptoms and gastrointestinal distress, and repeated or chronic exposure can lead to anemia, liver damage, and kidney damage. Camphor-based mothballs carry a lower poisoning risk overall, but large amounts can overstimulate the nervous system and cause seizures.
Symptoms of Mothball Poisoning
The first signs are almost always gastrointestinal. Naphthalene irritates the digestive tract on contact, so vomiting, diarrhea, abdominal pain, and loss of appetite typically appear before anything else. One telltale sign: your dog’s breath may smell like mothballs.
If the exposure is more significant, symptoms escalate. Watch for:
- Pale or brownish gums, a sign that red blood cells are being destroyed or can no longer carry oxygen properly
- Weakness or lethargy
- Labored or unusually fast breathing
- Walking off balance, trembling, or tremors
- Seizures in severe cases
Dogs who develop liver damage may show additional signs: dark urine, yellow discoloration of the eyes or skin, changes in stool color, and an increased tendency to bleed. These symptoms can take longer to appear and indicate serious internal damage that needs immediate veterinary attention.
Fumes Are a Risk Too
Mothballs work by slowly releasing vapor, which is what kills moths. That same vapor is harmful to dogs. While ingestion is the most dangerous route of exposure, a dog living in a home where mothballs are used in open spaces, under furniture, or scattered in rooms is breathing in those chemicals continuously. Prolonged inhalation can irritate the respiratory tract and, over time, contribute to the same organ damage seen with ingestion. Dogs kept in poorly ventilated areas where mothballs are present face the highest risk from fumes alone.
This is why using mothballs as a general pest deterrent, placing them around the yard, in the garage, or under the house, is especially risky for pet owners. Mothballs are designed to be used in sealed containers like garment bags or closed storage bins, not scattered in open areas where a dog can sniff, lick, or eat them.
What to Do If Your Dog Eats a Mothball
Time matters. If you know or suspect your dog has eaten a mothball, contact your veterinarian or an emergency animal poison hotline right away. Try to identify the type of mothball involved, since the active ingredient determines how your vet will approach treatment. If you have the packaging, bring it with you.
Do not try to induce vomiting at home unless specifically instructed by a veterinarian. Camphor-based mothballs in particular can cause seizures, and vomiting during a seizure creates a choking risk. Your vet will decide on the safest approach to decontamination based on what was ingested, how much, and how long ago.
Dogs treated quickly after a small exposure generally recover well. More severe cases involving significant red blood cell destruction or organ damage may require hospitalization, blood transfusions, or extended supportive care. Kidney and liver damage, when it occurs, can have lasting effects.
Safer Ways to Protect Clothing From Moths
If you have dogs in your home, there are effective alternatives that carry no poisoning risk. Cedar is one of the most widely used options: cedar blocks, cedar chips in sachets, or cedar-lined closets and storage bins repel moths naturally. The oils in cedar wood are what deter the insects, and they’re safe around pets.
Lavender sachets also repel moths and can be tucked into drawers or hung in closets. Storing seasonal clothing in airtight bags or sealed plastic bins prevents moths from reaching fabric in the first place, which eliminates the need for any chemical deterrent. Keeping clothes clean before storing them is another practical step, since moths are attracted to natural fibers that carry body oils and sweat.
If you currently have mothballs in your home, remove them from any area your dog can access. Even mothballs that have partially dissolved still contain enough active chemical to be dangerous. Ventilate the area thoroughly after removal, as residual fumes can linger in enclosed spaces for some time.