By Dial A Vet Veterinary Team
Most dogs pull a face and back away after one taste of lemon, which is nature doing its job. Lemon flesh is not highly toxic, and a dog that licks a slice will usually be fine apart from some drooling. The parts that cause trouble are the peel, the pips, the leaves and stems of the tree, and concentrated lemon products. These contain citrus essential oils and compounds called psoralens, which can upset the stomach and irritate the skin. Lemon has no place in a dog's diet, and some lemon products are best kept well out of reach.
Key takeaways
- Lemon flesh is very acidic and offers dogs no benefit. A small taste is unlikely to cause serious harm.
- The peel, seeds, leaves and stems contain essential oils and psoralens, which are listed as toxic to dogs.
- Eating these can cause vomiting, diarrhoea, drooling and lethargy. Skin contact may cause irritation, sometimes worse in sunlight.
- Lemon essential oil, citrus cleaners and lemon-scented products are more concentrated and riskier.
- Whole lemons, especially for small dogs, can also be a choking or blockage risk.
- Related: vomiting and diarrhoea, toxic and safe plants for pets.
What makes lemons a problem
The lemon tree and its fruit contain two groups of compounds that matter for dogs:
- Essential oils such as limonene and linalool, found mostly in the peel and leaves. These can irritate the gut and, in larger amounts, may cause weakness and depression.
- Psoralens, which can cause gastrointestinal upset and make skin more sensitive to sunlight (photosensitisation).
The fruit flesh mostly contains citric acid. It is sour and can upset a sensitive stomach, but it is the peel and plant material that carry most of the risk.
Backyard lemon trees
Lemon trees are a fixture of Australian backyards, and dropped fruit is a common chew toy. Dogs that tear into fallen lemons often swallow peel and pips. Puppies that chew leaves and twigs may get a mouthful of oils too. Mouldy windfalls can also carry other toxins. If your dog likes to scavenge under the tree, picking up fallen fruit regularly is the simplest fix.
Lemon products around the home
- Lemon essential oil and diffusers. Concentrated oils are the bigger concern. Dogs that lick spilled oil or get it on their coat can show drooling, vomiting, wobbliness and skin irritation. Do not use essential oils on dogs.
- Citrus-based cleaners and sprays. These often contain d-limonene and other ingredients. Keep pets away until surfaces are dry.
- Lemon juice, lemonade and lemon cordial. Very acidic and sugary. Some diet versions may contain artificial sweeteners, so check labels.
- Lemon desserts. Lemon tart, curd and slice are rich in butter, sugar and sometimes sweeteners.
Signs to watch for
- Drooling and lip licking
- Vomiting or diarrhoea
- Reduced appetite or a sore tummy
- Lethargy or seeming flat
- Red, irritated skin, particularly on lightly furred areas exposed to the sun
- Wobbliness or weakness after contact with concentrated oil
When it is an emergency
Contact your vet urgently if your dog has eaten a large amount of peel or plant material, swallowed a whole lemon (especially a small dog), licked or been coated in lemon essential oil or a citrus cleaner, or shows repeated vomiting, weakness, wobbliness, tremors, breathing difficulty or collapse. The Animal Poisons Helpline (1300 869 738) can advise on household products. Do not try to make your dog vomit at home.
How vets assess and treat it
Your vet will ask what part of the lemon or which product was involved, and how much. Bring the label for any cleaning or oil product. Most dogs that ate lemon fruit need only monitoring and supportive care for stomach upset. Dogs exposed to concentrated oils may need decontamination of the skin and coat, fluids and monitoring of liver values. If a whole lemon is suspected to be stuck, imaging and removal may be needed. Treatment depends on the dog and the exposure.
Prevention
- Pick up fallen lemons and fence off trees for dogs that scavenge.
- Store essential oils and citrus cleaners in a closed cupboard.
- Keep dogs out of rooms while cleaning with citrus products, until surfaces are dry.
- Do not rub lemon juice into a dog's coat or use it as a flea remedy.
Myths about lemon and dogs
"Lemon water helps dogs detox." No. Dogs do not need lemon, and acidic drinks can upset the stomach and teeth.
"Lemon juice repels fleas." There is no reliable evidence for this. In Australia, fleas and paralysis ticks need vet-recommended prevention.
"A squirt of lemon stops barking." Spraying citrus at a dog's face can irritate eyes and does not address why the dog is barking. Positive training works better.
FAQ
My dog licked a lemon slice. Do I need to worry?
Usually not. Expect a sour face and maybe drooling. Watch for vomiting.
Is lemon toxic to dogs?
The ASPCA lists the lemon plant as toxic to dogs, mainly because of the oils and psoralens in the peel and plant. The flesh is less of a concern.
Can dogs have lemon cake?
It is best avoided. It is high in sugar and fat, and some recipes contain ingredients that are not safe for dogs.
What about other citrus like oranges and mandarins?
Small pieces of peeled orange or mandarin flesh are not toxic, but the peel and seeds can still cause stomach upset.
Talk with a vet
If your dog has chewed a lemon, licked a citrus product or seems unwell after getting into the garden, a Dial A Vet veterinarian can help you decide how urgent it is. Book a Dial A Vet consult.
References
- ASPCA Animal Poison Control Center. Toxic and Non-Toxic Plants: Lemon.
- ASPCA Animal Poison Control Center. People Foods to Avoid Feeding Your Pets.
- Merck Veterinary Manual. Toxicoses From Essential Oils in Animals.
- American Kennel Club. Can Dogs Eat Lemons?
- Animal Poisons Helpline (Australia and New Zealand), 1300 869 738.
Disclaimer: Educational only. This page does not replace an examination or advice from your own veterinarian. If you are worried about your pet right now, contact your local vet or nearest emergency animal hospital.