Camphor is toxic to dogs, and inhaling concentrated camphor vapors can cause symptoms ranging from nausea to seizures. While a brief, incidental whiff of a camphor-containing product like Vicks VapoRub is unlikely to cause serious harm, deliberately exposing your dog to camphor fumes or allowing prolonged inhalation in a closed space poses real risk. The greater danger, though, is ingestion, which dogs may attempt after being drawn to the strong scent.
Why Camphor Is Dangerous for Dogs
Camphor is a waxy compound found in many over-the-counter products: vapor rubs, muscle balms, mothballs, and some essential oil blends. It’s rapidly absorbed through mucous membranes, the digestive tract, and even skin. Once in the bloodstream, a dog’s liver processes camphor through the same pathways it uses for many other compounds, but dogs metabolize it less efficiently than humans do. The substance crosses into the brain quickly, which is why neurological symptoms like disorientation and seizures appear in serious cases.
The Pet Poison Helpline lists camphor as a toxin for pets, with clinical signs that include nausea, vomiting, diarrhea, depression, and, in large exposures, seizures. In the most severe cases, death can occur from respiratory depression or uncontrolled seizures. The lethal oral dose in dogs is reported to be between 9 and 14 grams, but toxic effects can begin well below that threshold, especially in smaller breeds.
Inhalation vs. Ingestion: Which Is Worse?
Most documented cases of camphor poisoning in dogs involve ingestion, not inhalation. A dog chewing open a jar of vapor rub or swallowing a mothball delivers a concentrated dose directly to the stomach, where absorption is fast and complete. Inhalation delivers a much smaller amount of the compound into the bloodstream per minute, so brief, casual exposure to camphor vapors in a well-ventilated room is far less dangerous.
That said, inhalation is not harmless. Camphor vapors irritate the airways and can trigger coughing, watery eyes, and nasal discharge. In a small, enclosed space like a bathroom with a running humidifier containing camphor, a dog could inhale enough to cause gastrointestinal upset or lethargy. Dogs also have a much more sensitive sense of smell than humans, and what feels mildly mentholated to you can be overwhelming and distressing for your dog. Prolonged exposure in a poorly ventilated room increases the dose steadily over time.
Common Household Sources
The products most likely to expose your dog to camphor include:
- Vapor rubs and chest balms (typically 4 to 5 percent camphor)
- Mothballs and moth flakes (can be nearly pure camphor or naphthalene)
- Muscle pain ointments (variable concentrations)
- Essential oil diffusers (camphor oil or blends containing it)
- Some insect repellents
The real risk with many of these products is that a dog investigates the strong smell and then licks or eats the source. A vapor rub left open on a nightstand or a used tissue smeared with balm on the floor can be enough to tempt a curious dog. Diffusers running camphor oil in a small room combine both inhalation exposure and the possibility that a dog will knock over and lick the liquid.
Signs Your Dog Has Been Affected
Symptoms can appear within minutes to a couple of hours after significant exposure. Mild cases typically involve drooling, nausea, or vomiting. You might also notice your dog pawing at their nose or sneezing repeatedly if the exposure was primarily through inhalation. More concerning signs include:
- Vomiting or diarrhea
- Lethargy or unusual quietness
- Unsteady walking or disorientation
- Muscle tremors or twitching
- Seizures (in severe poisoning)
Seizures and respiratory difficulty are emergencies. But even milder symptoms like persistent vomiting or unusual drowsiness after camphor exposure warrant a call to your vet or a poison control hotline. The ASPCA Animal Poison Control Center (888-426-4435) and the Pet Poison Helpline (855-764-7661) both operate around the clock.
What to Do After Exposure
If the exposure was inhalation only, move your dog to fresh air immediately. Open windows, turn off any diffuser, and get them to a well-ventilated area. Watch for the symptoms listed above over the next few hours. Most dogs that simply walked through a room with mild camphor vapors will be fine, but if you notice vomiting, wobbliness, or behavior changes, call your vet.
If your dog ingested a camphor product, do not try to induce vomiting on your own. Camphor can cause seizures, and vomiting during a seizure creates a serious aspiration risk. Call your veterinarian or one of the poison control hotlines right away. Be ready to provide the product name, ingredient list, your best estimate of how much was consumed, and your dog’s weight.
Keeping Your Dog Safe
The simplest approach is to keep camphor products out of reach and avoid using camphor-based items in rooms where your dog spends time. If you use a vapor rub when you’re sick, apply it behind a closed door and wash your hands before petting your dog. Store mothballs in sealed containers in areas your dog cannot access. If you use an essential oil diffuser, check the ingredient list and skip camphor oil entirely if you have pets.
Some people use camphor-containing products as home remedies for dogs, applying small amounts to their paws or near their noses for congestion. This is not safe. Dogs will almost always lick their paws, converting a skin exposure into an oral dose. There are no veterinary guidelines supporting the use of camphor on or around dogs for any purpose.