Mothballs and Dogs:
Risks, Signs, and What to Do

If your home smells like mothballs, and you have cats, you should take it seriously. Mothballs and cats can have a dangerous overlap because cats investigate, lick, and groom residue, and they also breathe fumes in enclosed spaces. Even a small exposure can turn into vomiting, breathing trouble, or neurologic symptoms. Knowing what to look for and what to do right away can protect your pet.

For more help, see our Mothballs and Pets: Cat/Dog Safety, Risks, and Better Options guide.

What mothballs are and why they’re dangerous for pets

Mothballs are pest repellents made to release chemicals that deter insects. Those same chemicals can poison pets, especially when products are stored where a cat can access them, or when fumes build up in a closet, drawer, or garage. Cats are at extra risk because they groom their paws and fur after walking through residue.

How mothballs work and what chemicals they contain

Mothballs work by slowly releasing active chemicals into the air (a process called sublimation). The most common types contain either naphthalene or paradichlorobenzene. When pets inhale those fumes, lick residue, or ingest pieces, the chemicals can damage internal organs and disrupt normal body chemistry. The severity depends on the product type, the amount involved, the space size (how confined the fumes were), and how quickly treatment starts. Keep the product label if you have it, because the active ingredient helps a veterinarian choose the best plan.

Why dogs and cats are both at risk

Dogs and cats can both be poisoned by mothballs, and exposure often happens in the same ways, including eating a mothball, licking treated storage areas, or breathing vapors in a small room. Cats have a higher risk from residue because they groom constantly and they explore at nose level. If mothballs are placed in a closet, laundry bin, or under a bed, a cat can make contact with treated surfaces and transfer chemicals to their mouth. Dogs are more likely to chew or swallow mothballs directly, especially if the container is reachable.

Where exposure usually happens in the home or yard

Exposure commonly happens anywhere mothballs are stored or used in a way that allows contact or confinement of fumes. Look at closets, drawers, garment bags, and storage bins. Garages, basements, and sheds are also risky if the product is used outdoors but stored nearby in a way a pet can access. Loose placement in a room or on shelves increases licking and chewing opportunities. In contrast, sealed containers reduce odor and contact, but only if the pet cannot open them.

How mothball poisoning happens

Mothball poisoning occurs through direct ingestion, inhalation of vapors, contact with treated surfaces that a pet later grooms, or secondary exposure from items stored in the same area. Symptoms can appear quickly or progress after delayed absorption, which is why acting fast matters even when your pet seems normal at first.

Ingestion: eating mothballs or mothball residue

Ingestion is the most straightforward route. A dog may chew and swallow mothballs, or bite into a container with accessible product. A cat may eat a mothball directly, or ingest residue from a closet shelf, folded clothes, or a storage tote. Even small amounts can cause illness, especially with naphthalene or paradichlorobenzene. If you find a mothball missing, wet drool on the floor, or mouth irritation, treat it as exposure and contact a vet. Save any remaining pieces in a sealed bag so you can describe the product.

Inhalation: breathing fumes in enclosed spaces

Fumes are dangerous when air cannot circulate. A cat confined in a small closet, laundry room, or vehicle where mothballs are stored can inhale high chemical concentrations. Inhalation can irritate the nose and throat and contribute to poisoning when exposure continues. Signs often include coughing, gagging, wheezing, and lethargy. The longer the exposure in a poorly ventilated space, the higher the risk. Move your pet to fresh air first, then follow guidance from a veterinarian or poison resource.

Skin or paw contact and grooming afterward

Mothballs and residue can cling to paws, fur, or skin oils. A cat then grooms the treated area and transfers chemicals to the mouth, which turns contact into ingestion. You may notice paw staining, strong mothball odor on fur, or repeated licking. In dogs, residue can be picked up from surfaces like closet shelves and then swallowed during grooming. If you suspect skin or paw exposure, prevent further licking while you contact a professional, and be careful not to bathe your pet without instructions if a vet asks you to wait.

Secondary exposure from treated clothing, bedding, or storage areas

Pets can be poisoned by items that smell strongly even after the initial placement. Clothes, blankets, bedding, and towels stored with mothballs can transfer residue to the pet’s fur and then to their mouth. This often happens when owners handle the items and later pets jump onto treated surfaces. In storage rooms, odors can build in fabric and carpets, creating a lingering exposure source. Wash items according to label directions and keep mothballs sealed and inaccessible in the meantime.

Warning signs to watch for in dogs and cats

Mothball poisoning can start with subtle changes and escalate quickly. Watch closely for GI upset, breathing changes, and neurologic signs, especially after a suspected access to mothballs or treated storage areas. If you see more than one body system affected, treat it as urgent.

Early symptoms that can look mild at first

Early signs can include drooling, vomiting, loss of appetite, lethargy, and unusual hiding or restlessness. You may also see diarrhea or repeated lip-licking, which can suggest mouth or throat irritation. Some pets show mild breathing discomfort or appear “off” before obvious vomiting begins. For cats, you might notice extra grooming, paw licking, or reduced interest in food. Because symptoms can progress after a delay, any suspected exposure should trigger a call to a veterinarian or poison resource even if your pet looks okay right away.

Neurologic signs such as wobbliness, tremors, or seizures

As poisoning worsens, pets can develop neurologic symptoms. Watch for wobbliness, ataxia (staggering or poor coordination), tremors, or muscle twitching. Severe cases can include seizures, sudden collapse, and extreme weakness. These signs are concerning because they often indicate significant toxicity and urgent effects on the body’s chemistry. If your pet is unsteady, actively shaking, or having seizures, you need emergency care immediately. Keep the pet safe from falls, but do not restrain in a way that causes injury.

Digestive and breathing symptoms

Digestive symptoms may continue or worsen, including repeated vomiting, abdominal discomfort, and diarrhea. Breathing symptoms can include coughing, gagging, wheezing, or rapid breathing. Because inhalation irritates the respiratory tract, you may notice a hoarse sound or labored breathing. Some cats show open-mouth breathing or appear unable to catch their breath. If your pet is struggling to breathe, pale, or suddenly weak, treat it as an emergency rather than waiting for symptoms to pass.

When symptoms become an emergency

Symptoms become an emergency when there are red-flag signs like seizures, severe wobbliness, collapse, or trouble breathing. Pale or bluish gums also signals a serious problem with oxygen delivery. Repeated vomiting with weakness, inability to keep fluids down, or rapidly worsening lethargy are urgent because dehydration and toxin effects can accelerate. Any suspected ingestion of multiple mothballs, even if early signs are mild, deserves immediate professional guidance. Time matters for preventing lasting liver and blood damage.

What to do immediately if your pet may have been exposed

Act quickly and keep it simple. Your goal is to stop exposure, reduce ongoing fumes or residue contact, and get tailored instructions from a vet or poison resource. Do not improvise treatments at home.

Move your pet away from the source right away

Get your pet out of the area with mothball odor and away from treated items. Take them to a well-ventilated room, and if possible, outdoors in fresh air. Prevent the pet from returning to the storage area while you set up the phone call. If residue may be on paws or fur, limit contact and avoid letting the pet rub against furniture. Keep them calm and still to reduce additional irritation from fumes. The faster you end exposure, the less toxin absorption can continue.

Do not induce vomiting unless a vet tells you to

Do not make your pet vomit unless a veterinarian or poison expert instructs you. Inducing vomiting can be unsafe depending on the product, the pet’s condition, and whether chemicals have already irritated the mouth and throat. It can also increase risk of aspiration, meaning the substance goes into the lungs instead of the stomach. Even when vomiting seems like a good idea, follow professional guidance based on the active ingredient and the amount involved.

Gather the product label and estimate how much was exposed

Find the mothball container or product label so you can tell the vet the active ingredient, such as naphthalene or paradichlorobenzene. Estimate exposure based on what you observed, including how many mothballs are missing, whether you found chewed pieces, or how strong the smell was in a confined space. If clothing or bedding is involved, note how long it was stored with mothballs and whether the pet had access to the fabric. Take a photo of the label if you can. This information helps the vet estimate risk and decide on specific treatments.

Call your veterinarian, an emergency clinic, or poison control

Call immediately, even if your pet seems normal. Provide the phone operator with your pet’s species, age, weight, what you suspect (ingestion, inhalation, or contact), and the active ingredient from the label. Tell them what symptoms you see and when exposure happened. Follow the instructions closely and do not wait for symptoms to worsen at home. If your primary vet is closed, use an emergency clinic or a pet poison hotline so you get fast, specific guidance.

How veterinarians treat mothball exposure

Veterinary treatment focuses on stopping ongoing absorption, protecting the body from chemical damage, and monitoring for delayed complications. The exact plan depends on the toxin type, the route of exposure, and the severity of symptoms.

What the vet needs to know during triage

During triage, the vet will ask about timing, type of exposure (swallowing, breathing fumes, or contact), and the mothball active ingredient. Be ready to provide your pet’s weight, your pet’s species (dog or cat), and any symptoms like vomiting, drooling, coughing, or wobbliness. Bring the product label or a clear photo. If you have an estimate of how many mothballs were involved or how long the pet was in a confined space, share that too. The vet uses this to estimate risk and decide how aggressive treatment needs to be.

Common supportive treatments and monitoring

Supportive care is central. The vet may start oxygen support if breathing is affected, provide anti-nausea medication for vomiting, and use IV fluids for dehydration or poor intake. Bloodwork and urine tests are often used to check organ effects and overall stability. In some cases, activated charcoal may be discussed depending on timing and what was ingested. Throughout treatment, the veterinary team monitors vital signs closely because symptoms can worsen as toxins affect the body’s chemistry.

Why fast treatment matters for liver and red blood cell damage

Many mothball poisonings can harm the liver and can cause red blood cell damage, which affects how well oxygen moves through the body. Delayed effects are one reason professionals want you to call immediately, even if your pet seems okay at first. Early intervention can reduce ongoing absorption and limit the extent of organ injury. Blood monitoring is important because changes may not appear instantly. Fast treatment also helps guide whether specific antidotal or targeted therapies are needed for your pet’s exact situation.

How to prevent future pet exposure

Prevention is the real win. A few storage changes can remove access, reduce residue transfer, and stop odor from building up in spaces your cats explore. Keep the “no contact” rule, and never rely on smell alone to indicate safety.

Safer storage and disposal of mothballs

Store mothballs in a fully sealed, hard-sided container in a location your pet cannot reach. Use a container with a secure lid, not a cardboard box, and keep it on a high shelf or in a locked cabinet. Never place mothballs loose in closets, drawers, garages, or under furniture. Dispose of mothballs safely according to your local guidance, and do not keep them long term just because they still smell. Replace mothballs only when the product is sealed and the pet has no access.

Pet-safe alternatives for clothes, closets, and storage bins

Consider alternatives that do not involve toxic chemicals. Cedar blocks or cedar chips can help deter pests, and they are commonly used for closets and storage. For fabrics, clean and store items in sealed garment bags, vacuum-sealed bags, or airtight totes. Regular washing and drying reduces insect attraction. For ongoing pest control, use non-toxic traps or professional pest management focused on safe indoor practices. Choose storage solutions that remove moth access rather than relying on odor.

Why outdoor use and loose placement are especially risky

Outdoor mothball use can still be risky if mothballs are stored or left within reach indoors. Cats can carry residue on paws after exploring a treated area, then groom and ingest it. Loose placement increases contact chances, including brushing against treated surfaces, knocking mothballs around, or chewing accessible pieces. Even if the goal is only to protect items outdoors, storage habits and access points matter. Keep any repellent products sealed and out of reach, indoors or out.

Household rules for homes with both dogs and cats

Set strict rules so pets never have a chance to access stored products. Keep mothball containers inside locked storage, and prevent pets from entering rooms where mothballs are used or stored. When handling treated clothes or bins, keep your pets in a different room until the items are back in sealed storage. For dogs, leash management around storage areas can prevent chewing. For cats, block access to closets and under-bed storage, and choose airtight bins for all clothing and bedding.

When to seek emergency help versus routine advice

Use symptom severity and exposure type to decide how urgently you need help. Some cases require immediate emergency care, while others can begin with same-day guidance. If you are unsure, contact a vet or poison resource right away.

Red-flag symptoms that need immediate care

Seek emergency care for seizures, severe wobbliness, collapse, or inability to stand. Trouble breathing, open-mouth breathing, persistent coughing, or a sudden change in breathing pattern are emergencies. Pale or bluish gums also signals urgent oxygen-related complications. Repeated vomiting plus extreme weakness counts as urgent, especially if your pet cannot keep fluids down. If you suspect ingestion of multiple mothballs or heavy exposure in a confined area, treat it as an emergency even if symptoms have not started yet.

Situations that still warrant a same-day vet call

Call a veterinarian the same day if your pet had a suspected nibble, if residue was on fur or paws, or if you notice mild vomiting, drooling, or lethargy. A strong odor in a closed closet or car with your cat inside also warrants same-day advice. If your pet swallowed a small piece or you cannot estimate the amount, the safest move is to get professional guidance promptly. Even mild early symptoms can progress, so same-day contact helps prevent delays in treatment.

What to mention when you call for help

When you call, give your pet’s species, weight, age, and the exact product details from the label if you have them. Describe the route of exposure, such as ingestion (chewing or swallowing), inhalation (time in a confined space), or contact (fur, paws, or treated clothes). Share the timing, when you noticed the mothballs, and when symptoms started. List current symptoms, including vomiting, drooling, coughing, wobbliness, or appetite changes. Finally, tell them what steps you already took, like moving your pet to fresh air.

Frequently Asked Questions

Are mothballs toxic to both dogs and cats?

Yes. Both dogs and cats can be poisoned by mothballs, especially if they eat them or inhale fumes in a confined area. Cats are often more vulnerable because they groom residue from their fur and paws, which turns contact into ingestion.

What are the first signs of mothball poisoning in pets?

Early signs can include vomiting, drooling, lethargy, loss of appetite, and unusual behavior. More severe cases may progress to wobbliness, tremors, trouble breathing, pale gums, or seizures.

Should I make my pet vomit after eating a mothball?

No, not unless a veterinarian or poison expert specifically instructs you to do so. Inducing vomiting can be unsafe and may worsen the situation depending on the product and your pet’s condition.

How quickly should I act if my dog or cat was exposed?

Act immediately. Contact a veterinarian or pet poison helpline as soon as possible, even if your pet seems normal at first. Some toxic effects can be delayed.

Can pets get sick just from smelling mothballs?

Yes. Strong fumes in a poorly ventilated area can irritate the respiratory system and contribute to poisoning, especially with prolonged exposure.