Are Scented Candles Safe for Dogs? What the Evidence Says
Key Takeaways
- Dogs are not cats. Cats carry a genetic defect that leaves them unable to process certain fragrance compounds. Dogs don't have it, and the difference is large (Court, Vet Clin North Am Small Anim Pract, 2013).
- That doesn't make dogs immune. Eucalyptus, tea tree, camphor, clove and wintergreen are all named as hazardous to pets by Australia's Animal Poisons Centre.
- How your dog meets the oil matters more than whether it's in the room. The Animal Poisons Centre says risk depends on the type of oil, its concentration, and the route of exposure. The severe cases they describe involve swallowing concentrated oil or getting it on the coat.
- The risk most owners underrate isn't the fragrance. It's the flame. 67% of fatal house fires in Victoria in 2024 started in the living room or bedroom — the two rooms where people burn candles (CFA and Fire Rescue Victoria, August 2025).
- If your dog has swallowed candle wax or fragrance oil, ring the Animal Poisons Helpline on 1300 869 738. It's free, and it's staffed by toxicologists.
If you've searched this before, you've probably found two kinds of answer. One says candles are dangerous for all pets. The other says they're fine. Neither is much use when you're standing in your lounge room holding a candle and looking at your dog.
Here's what the veterinary and toxicology evidence actually supports.
The short answer
For most dogs, in a ventilated room, a candle burning out of reach is a low-risk thing. The evidence does not support treating a lit candle the same way you'd treat a bottle of concentrated essential oil.
Three things change that answer: which oils are in the fragrance, how your dog could actually come into contact with them, and whether the candle can be knocked over.
The rest of this article works through those in turn. The last one is the most underrated, and it's where this ends up.
Dogs are not cats, and the difference is genetic
This is the part most pet-and-candle articles get wrong, usually by treating both species as one category called "pets."
Glucuronidation is one of the main ways a mammal's liver packages up a foreign compound so the body can excrete it. It's handled by a family of enzymes called UDP-glucuronosyltransferases, or UGTs.
Cats are missing some of them. A 2013 review in Veterinary Clinics of North America: Small Animal Practice describes the feline UGT1A6 gene as carrying "multiple mutations in all cats." It's a pseudogene — a permanently disabled copy. Cats lack both UGT1A6 and UGT1A9 (Court, 2013).
The scale of the gap is worth stating plainly. That same review reports dogs express up to 10 different UGT1A enzymes. The feline version of the gene has only two functional copies.
The defect matters most for compounds with what the paper calls "a simple planar phenolic structure." A lot of fragrance chemistry is phenolic. That is the real reason cats keep appearing in essential-oil poisoning warnings and dogs appear less often.
So when you read that essential oils are dangerous for pets, a fair amount of that warning was written with cats in mind. If you have both, our guide to candles and cats is the one to read.
This does not mean dogs are safe by default. Dogs process these compounds better. They still get poisoned by them.
Which oils actually matter
Australia's Animal Poisons Centre is a free toxicology service for pet owners and vets. Its guidance names specific oils rather than warning about essential oils in general, which makes it far more useful.
| Oil | What the Animal Poisons Centre reports |
|---|---|
| Eucalyptus | Ingestion can cause drowsiness, unsteadiness, confusion, coma and seizures |
| Tea tree | Same effects as eucalyptus. Severe poisoning including liver damage reported in dogs and cats when concentrated oil was applied to skin |
| Camphor | Stimulates the central nervous system; causes seizures |
| Clove | Depresses the central nervous system; causes liver injury |
| Wintergreen | High methyl salicylate content — abdominal pain, vomiting, panting, confusion, seizures, coma and death |
Source: Animal Poisons Centre, Essential Oils and Pets
Eucalyptus deserves a note for Australian readers. It turns up in local fragrance blends more than it does overseas, and it's on that list.
If a candle's fragrance is disclosed, you can check it against those five names before you buy. If it isn't disclosed, you can't — and that's worth knowing about a product you're about to burn in a room your dog sleeps in.
Full disclosure: we make candles. Ours are scented with fragrance oils rather than essential oils. That's a composition fact, not a safety claim. It matters here only because the warnings above are about essential oils specifically. Fragrance oils carry their own aroma chemicals, and the same questions of concentration and exposure still apply.
Exposure route changes the risk more than most people expect
The Animal Poisons Centre is explicit that risk isn't a fixed property of an oil. It "is dependent on many factors including the type of essential oil, the concentration of the oil and how your pet is exposed to the oil (ingestion, inhalation, skin exposure etc)."
Read the severe cases in that guidance and a pattern shows up. The liver damage was from concentrated oil applied to skin. The seizures and coma were from ingestion.
A candle is a different proposition from a bottle. The fragrance load is diluted through the wax, released slowly, and dispersed into the volume of a room.
That isn't a claim that inhaling fragrance is harmless. It's a claim about proportion: the exposures that put dogs in veterinary hospitals are concentrated ones, and a burning candle out of reach isn't that.
The practical version — a burning candle your dog can't get to is a different risk from an oil bottle your dog can knock over. Store the bottles properly. Both the Animal Poisons Centre's advice on ventilation and its advice on keeping containers away from pets point the same way.
Ventilate the room. The Animal Poisons Centre's advice is to use burners and vaporisers "only in well ventilated spaces." A closed room concentrates whatever you put into the air. An open door or window undoes most of that.
The risk owners underrate: the flame, not the fragrance
Search for candles and dogs and you'll get pages about toxicity. The Australian fire services are worried about something more immediate.
Fire Rescue Victoria's advice is blunt: "please never leave a burning candle unattended." Candles belong "on stable, uncluttered surfaces that won't burn, and placed well away from curtains and other flammable materials" (CFA and FRV, August 2025).
That release also carries the statistic worth sitting with. 67% of fatal house fires in Victoria in 2024 began in the living room or bedroom. Those are exactly the rooms people put candles in.
Fire and Rescue NSW gives the same advice in slightly different words. Never leave candles "in places where they can fall or set alight flammable items such as curtains or upholstery." And "extinguish them if you leave the room and always before going to bed" (Fire and Rescue NSW).
Now add a dog to that picture. A wagging tail sits at coffee-table height on a lot of breeds. A dog that jumps up to greet someone can clear a side table. Neither fire service is writing about pets specifically, but "places where they can fall" describes a lounge room with a labrador in it fairly well.
This is the part of candle safety that doesn't depend on which wax or which fragrance you bought.
What to watch for, and who to call
Signs of essential-oil poisoning reported by the Animal Poisons Centre include drowsiness, unsteadiness on the feet, confusion, vomiting, panting, seizures and coma.
If your dog shows any of those, don't wait to see whether it passes. The same goes if you've seen them chew a candle, swallow wax, or get oil on their coat.
Animal Poisons Helpline (Australia): 1300 869 738. Free, and staffed by specialists in animal toxicology. Ring your vet as well if signs are already showing.
Wax itself is a separate question from fragrance, and one worth asking a professional about rather than a blog. If your dog has swallowed a quantity of wax, ring the helpline and describe what and how much.
Burning a candle safely around a dog
Nothing here is complicated. It's mostly about height and airflow.
- Put it where the dog can't reach it. Above tail height, back from the edge, on something stable that won't burn.
- Never leave it burning in an empty room. Both fire services say this. Extinguish it when you leave, and before bed. A snuffer does that without the splatter or smoulder you can get from blowing one out.
- Keep the wick trimmed. A short wick burns with a smaller, steadier flame. A wick trimmer is the tidy way to do it, but scissors work.
- Ventilate. Door open or window cracked, particularly in a small room.
- Check the fragrance against the five named oils if the maker discloses what's in it.
- Store concentrated oils out of reach — that's the exposure route behind the serious cases, not the candle.
- Give your dog somewhere else to be. If they choose to leave the room, let them. That's information.
- Be more careful if your dog has a respiratory condition. Talk to your vet first — that's a clinical question, not a candle question.
The honest summary
The evidence supports a moderate position, which is less satisfying than either extreme.
Dogs handle these compounds substantially better than cats, and the genetics of that are well documented. Specific oils are genuinely hazardous, and eucalyptus and tea tree are common enough in Australia to be worth checking for. The exposures that cause serious harm are concentrated ones. And the risk that actually burns houses down is an unattended flame, which has nothing to do with fragrance chemistry at all.
Put the candle up high, open a window, put it out when you leave the room, and keep the oil bottles in a cupboard.
Julia hand-pours the candles at Yarra Light in Melbourne. This article is general information, not veterinary advice — if you're worried about your dog, ring the Animal Poisons Helpline on 1300 869 738 or talk to your vet.