Lemongrass oil is not considered safe for dogs. The ASPCA classifies lemongrass (Cymbopogon citratus) as toxic to dogs, cats, and horses, with essential oils and cyanogenic glycosides identified as the toxic compounds. While a small, incidental exposure may only cause mild stomach upset, concentrated lemongrass essential oil poses real risks through both skin contact and ingestion.
Why Lemongrass Oil Is Harmful to Dogs
Lemongrass oil is highly concentrated. Its primary active ingredient is citral, a terpenoid that makes up 75 to 85 percent of the oil. The remaining fraction contains other biologically active compounds including geraniol, limonene, and citronellal. These are the same compounds that give lemongrass its strong scent, and they’re far more potent in essential oil form than in the fresh plant.
Dogs process plant compounds differently than humans do. Their livers are less efficient at breaking down certain volatile oils, which means even small amounts of a concentrated essential oil can build up and cause problems. PetMD lists lemongrass among the essential oils that can be toxic to dogs through both ingestion and skin exposure, advising pet owners to avoid it entirely.
Signs of Lemongrass Oil Exposure
The most common reaction is stomach upset: vomiting, drooling, or diarrhea. A retrospective study covering 2006 to 2008 found that plant-derived flea products containing lemongrass oil (at concentrations of 1.5 to 4.5 percent) alongside other essential oils caused adverse effects in dogs, including lethargy and vomiting. These weren’t dogs drinking the oil straight from a bottle. They were wearing commercial products formulated with diluted essential oils.
Skin irritation is another concern. Dogs that walk through a diffused mist or have undiluted oil applied to their coat may develop redness, itching, or chemical burns. Smaller dogs, puppies, and dogs with liver conditions are at higher risk because their bodies have even less capacity to handle these compounds.
What About Diffusing Lemongrass Oil at Home?
Passive diffusers (reed diffusers, for example) release a lower concentration of oil into the air and are generally less risky than active ultrasonic or nebulizing diffusers, which create a fine mist that can settle on your dog’s fur and be licked off during grooming. If you diffuse any essential oil in a home with dogs, make sure the room is well ventilated and your dog can leave the area freely. That said, lemongrass oil specifically is one that veterinary sources recommend avoiding around dogs altogether.
Lemongrass Oil as a Flea or Tick Repellent
Many pet owners look into lemongrass oil because they want a natural alternative to chemical flea and tick treatments. While citronella, a closely related oil, has shown strong results in lab settings (killing 100 percent of tick larvae at certain concentrations), lab results don’t translate directly to safe, real-world use on a living dog. The retrospective study mentioned above found that commercial flea products blending lemongrass with other essential oils caused enough adverse reactions to raise safety concerns. The researchers concluded that essential oils should only be used on dogs under veterinary supervision.
The appeal of “natural” pest control is understandable, but essential oils are potent chemical compounds. Natural does not mean gentle, especially for an animal whose body metabolizes these substances differently than yours.
What to Do if Your Dog Is Exposed
If your dog licks or ingests lemongrass oil, or if you notice signs like vomiting, excessive drooling, lethargy, or skin irritation after exposure, contact your veterinarian or a poison control hotline right away. The ASPCA Poison Control Hotline (888-426-4435) and the Pet Poison Helpline (855-764-7661) are both available 24/7.
Have the product label or bottle on hand when you call. Be ready to share the brand name, the ingredient list, how much your dog was exposed to, when it happened, and your dog’s approximate weight. Do not try to induce vomiting on your own. Cornell University’s veterinary college specifically warns that making a dog vomit is sometimes the wrong move and can make things worse depending on the substance involved. Let a professional guide you.
Safer Alternatives for Dogs
If you’re looking for pest control, talk to your vet about proven options. Prescription flea and tick preventives have been tested specifically for canine safety at known doses, which is something no essential oil product can claim with the same rigor.
If you simply enjoy aromatherapy and want to use oils that are less likely to harm your dog, some veterinary sources consider lavender and chamomile to be lower risk when properly diluted and used in well-ventilated spaces. Even with those, keeping the oil away from your dog’s skin and mouth is the safest approach. Lemongrass oil, however, belongs on the “avoid” list for households with dogs.