Laurie Anne Walden, DVM
Corneal ulcers are common causes of eye redness in dogs and cats. A corneal ulcer is an area of damage to the surface of the cornea, the clear structure at the front of the eye. These ulcers are painful but usually heal readily with treatment. Sometimes corneal ulcers develop complications that require surgery or other interventions.
Anything that scratches, hits, or irritates the surface of the eye can cause a corneal ulcer. Animals with low tear production are at increased risk for corneal ulcers because they have a low volume of tears to wash away irritants. These are some of the things that cause corneal ulcers:
Some animals have a defect of the corneal epithelium—the surface layer of corneal cells—that increases the risk of ulcers and keeps ulcers from healing. These slow-healing ulcers are called indolent ulcers. Corneal ulcers can become infected, threatening the animal’s vision. Deep corneal ulcers and wounds can penetrate all the way through the cornea and rupture the eye.
Eye medications that contain steroids (commonly used to treat conjunctivitis and other inflammatory eye conditions) prevent corneal ulcers from healing properly. Steroid-containing eye medications can also increase the risk of corneal infection.
The signs of eye discomfort are the same whether they are caused by a corneal ulcer or by another eye disorder. Typical signs are squinting, redness of the white part of the eye, and clear or cloudy eye drainage. The animal might rub the eye, and the cornea might look cloudy. Deep ulcers are sometimes visible without an ophthalmoscope and look like a dent or divot in the cornea. Superficial ulcers are usually not visible to the naked eye.
An animal with any of these signs should see a veterinarian right away. Although uncomplicated corneal ulcers are relatively minor, they are painful. Some of the conditions that cause the same signs are medical emergencies that require immediate treatment to save the eye.
Corneal ulcers are diagnosed with fluorescein dye applied to the eye. This green dye shows areas where the normal corneal epithelium is disrupted or missing. The eye is also examined under magnification to assess the depth and size of the ulcer, detect complications, and find the cause.
An uncomplicated ulcer is treated with eye medication to prevent infection and relieve pain. The animal might be fitted with a protective collar (the lampshade type) to prevent eye rubbing. The cause of the ulcer is also treated, if possible. The eye is rechecked with fluorescein dye after a few days to be sure the ulcer has fully healed.
Complicated ulcers are treated according to their cause and severity. Indolent ulcers are treated with a procedure to remove loose corneal epithelium. This procedure can often be performed in an awake animal with drops to numb the eye. Some indolent ulcers need a more extensive procedure with the animal under general anesthesia. Deep ulcers and wounds that might rupture the eye need surgical treatment by a veterinary ophthalmologist.
Image source: https://pixy.org/6427021/
Laurie Anne Walden, DVM
An outbreak of a highly infectious cough has recently been affecting dogs in the Charlotte area. The disease spreads quickly wherever dogs gather: boarding kennels, dog day cares, dog parks, and so forth. Dogs with no symptoms can spread the infection to other dogs.
Most dogs have mild illness and recover at home, but some dogs develop pneumonia and need to be hospitalized. Dogs with pneumonia are at risk of dying.
These are some of the signs of mild illness:
Call your veterinarian if your dog has any of the following signs:
Take your dog to an emergency clinic right away if your dog has signs of trouble breathing:
Many viruses and bacteria cause canine infectious respiratory disease complex (CIRDC), sometimes called kennel cough. Dogs are often infected with more than 1 agent at the same time.
These are some of the agents that cause CIRDC:
Core vaccines (standard for all dogs) give protection against some but not all of the viral agents. Noncore vaccines (optional lifestyle vaccines) are available for canine influenza virus and Bordetella. Vaccines don’t completely prevent CIRDC, but fully vaccinated dogs tend to have shorter and less severe illness. Vaccines also help limit spread of the disease.
Transmission and Risk Factors
The infectious agents spread through respiratory droplets and secretions. Some of the agents stay in the environment and continue to infect dogs for weeks. Dogs are infected by direct contact with an infected dog, by inhaling respiratory droplets, or by licking contaminated objects like bowls, bedding, toys, floors, walls, or people’s hands or clothes.
Because CIRDC can spread silently (by dogs with no symptoms) and some of the agents persist in the environment for a long time, outbreaks can be hard to control.
Any dog that has contact with other dogs or spends time in areas where dogs gather can be infected. Most dogs develop only mild illness and recover within a couple of weeks. Puppies, senior dogs, and dogs with impaired immune function are at higher risk of pneumonia.
Some of the agents that cause CIRDC can also infect cats. The only CIRDC agent known to infect humans is Bordetella, but transmission to people is very rare. Canine influenza is not contagious to people.
Diagnosis and Treatment
The decision to pursue diagnostic tests depends on the individual dog. Dogs with mild illness need physical examination but often don’t undergo other tests if they have symptoms that suggest CIRDC, have been around other dogs (especially in an area with an outbreak of respiratory disease), and are feeling well otherwise. Additional diagnostic tests can include chest radiographs, bloodwork, tests for specific infectious agents, and tests to rule out other causes of coughing.
Treatment can range from just resting at home to being hospitalized for intensive care, depending on the severity of illness. Antibiotics don’t kill viruses, but because CIRDC often involves a combination of organisms, dogs suspected to have a viral respiratory disease (like influenza) might receive an antibiotic as a precaution against bacterial infection.
These are some tips to help keep your dog safe from infectious respiratory disease:
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Image source: https://pixy.org/4653483/
Laurie Anne Walden, DVM
Dogs and cats can’t have pumpkin spice lattes or Halloween candy, but not all foods that we associate with fall are off the menu for our pets.
If you’d like to give treats to your pets, keep these precautions in mind:
Homemade and store-bought pet treats
Many recipes for homemade dog and cat treats are available. Making your own pet treats can be a fun family project and a great outlet for creativity. Kids might be surprised that their dog is so enthusiastic about a baked dog biscuit that tastes like cardboard to them. It’s a good reminder that pets don’t need the sugar, salt, and flavorings that humans prefer.
Pet food manufacturers know a marketing opportunity when they see one, so you can also find themed seasonal treats for sale. Store-bought pet treats are fine as long as they don’t contain a problem ingredient (always check labels).
Plain cooked or canned pumpkin is safe, and dogs and cats tend to like it. If you use canned pumpkin, be sure to get plain pumpkin and not pumpkin pie filling. The sugar and spices in pie filling can cause problems. Likewise, don’t give a pet a piece of pumpkin pie—and especially not sugar-free pie, which might contain xylitol.
White potatoes and sweet potatoes
Most dogs love potatoes of any type. Skip the butter, salt, and toppings, though: no loaded baked potatoes or sweet potato casserole for pets.
Other vegetables and fruits
Many vegetables and fruits (not grapes!) are safe, tasty, low-calorie treats for pets. As always, stick with plain, unseasoned items for animals. Avoid casseroles, which might contain problem ingredients like onion and fat. To avoid a choking risk, cut raw vegetables and fruits into small pieces and remove seeds, cores, and thick peels. These are some good options:
A bite of cooked lean poultry meat is safe for dogs and cats. Avoid giving pets skin, fat, bones, pan drippings, raw meat, or meat seasoned with onion.
Is popcorn a fall food? I think it depends on which Thanksgiving cartoons you watch. As with other foods, don’t add butter, salt, or seasonings to popcorn pieces you toss to your pets. Air-popped popcorn doesn’t have added fat, so it’s safer than oil-popped or microwaved popcorn for animals like schnauzers that have an increased risk for pancreatitis.
Photo by Amy Starr on Unsplash
Laurie Anne Walden, DVM
Intervertebral disk disease (IVDD), also referred to as slipped disk, ruptured disk, or herniated disk, is a relatively common cause of neck and back pain in dogs. Some dogs with IVDD also develop neurologic deficits like toes knuckled under, a wobbly gait, or the inability to walk. The prognosis depends on the severity of the injury and length of time before treatment. A sudden inability to walk is a medical emergency. Affected dogs might need urgent surgery.
The spine is a row of individual bones called vertebrae. The spinal cord runs along a bony canal through the vertebrae. Intervertebral disks sit between the vertebrae just below the spinal cord and provide cushioning and support for the spine.
Intervertebral disks are sort of like jelly doughnuts: they have a squishy interior (the nucleus pulposus) and a firmer, protective exterior (the annulus fibrosus). With IVDD, part of a disk herniates; it leaks or bulges beyond its normal location and presses on the spinal cord or on the surrounding nerves.
Types of IVDD
IVDD is classified according to the type of disk herniation. Type 1 IVDD has a genetic link: it’s most common in dog breeds with chondrodystrophy, which usually means dogs with short legs and a long back. In type 1 IVDD, the nucleus pulposus becomes mineralized (hardens) over time and eventually breaks through the annulus fibrosus into the spinal canal, bruising the spinal cord. This type of herniation can happen quickly, causing sudden symptoms. Affected dogs are often young adults.
Type 2 IVDD is caused by age-related breakdown of the annulus fibrosus. Weakening of the annulus fibrosus allows the disk to bulge upward against the spinal cord. Type 2 IVDD is more gradual than type 1 and is more common in older dogs. Intervertebral disk herniation can also be caused by trauma or strenuous exercise.
Dogs at Risk
Any dog can develop IVDD. These are the breeds at highest risk for type 1 IVDD:
Type 2 IVDD is more common in larger dogs like these:
The symptoms of IVDD range from pain to paralysis, depending on the severity of herniation, the force with which the herniated disk material hits the spinal cord, and the duration of the injury. The mildest form of IVDD is neck or back pain with ability to walk and no neurologic deficits. Neck pain can cause limping, so the symptoms of a herniated disk in the neck can be mistaken for an orthopedic problem.
More severe spinal injuries progress through stages that worsen with time: limb weakness, neurologic deficits, inability to walk, inability to stand, inability to move the limbs, and finally inability to feel pain in the limbs. Dogs with spine injuries might lose their normal bladder and bowel function.
These are some of the symptoms of IVDD:
A physical examination shows whether the patient has neurologic deficits and often reveals the approximate location of the injury in the spine. Advanced imaging techniques like computed tomography or magnetic resonance imaging are required to make a definite diagnosis and locate all of the affected disks. Radiographs (x-ray images) are less helpful for diagnosing IVDD but might be obtained to rule out other possible causes of the symptoms, like fractures, dislocations, bone infection, and cancer.
Dogs with milder symptoms—pain, ability to walk, and no or mild neurologic deficits—are usually treated medically at first. A crucial part of medical management is restricting the dog’s activity to allow the annulus fibrosus to heal, similar to treating a sprain. Some dogs need strict crate confinement. Medical management also includes medication to relieve pain. Dogs that begin to feel better with pain medication can reinjure themselves if they resume normal activity too soon, so they usually need to continue strict activity restriction for weeks.
Dogs with neurologic deficits or pain that doesn’t improve with medical management often need surgery to remove herniated disk material and relieve pressure on the spinal cord. Time is of the essence; the longer the injury to the spinal cord is present, the worse the neurologic deficits and the worse the prognosis for recovery.
For dogs that can’t walk but can still feel sensation in their feet, surgery performed as soon as possible after symptoms begin typically gives the best chance of being able to walk again. Once pain sensation in the feet is lost, the odds of recovery are much lower even with surgery. Spine surgery is expensive and dogs need extensive physical rehabilitation afterward, so the decision to proceed with surgery depends partly on the dog owner’s financial situation and ability to provide long-term care.
Olby NJ, Moore SA, Brisson B, et al. ACVIM consensus statement on diagnosis and management of acute canine thoracolumbar intervertebral disc extrusion. J Vet Intern Med. 2022. doi:10.1111/jvim.16480
Spinella G, Bettella P, Riccio B, Okonji S. Overview of the current literature on the most common neurological diseases in dogs with a particular focus on rehabilitation. Vet Sci. 2022;9(8):429. doi:10.3390/vetsci9080429
Photo by PublicDomainPictures on Pixabay
Laurie Anne Walden, DVM
Canine parvovirus is highly contagious among dogs. Infection causes severe illness and is often fatal in dogs that do not receive intensive treatment.
Parvovirus infection is most common in puppies that have not yet completed their initial vaccination series and in adult dogs that are not fully vaccinated against parvovirus. A recent outbreak of parvovirus in Michigan highlighted how quickly the virus can spread, especially in dogs in group housing like animal shelters. All dogs are at risk of infection, but whether a dog becomes ill depends on the dog’s level of immunity to the virus.
Canine parvovirus type 2 (the version responsible for illness) infects domestic dogs and some wild animals, such as foxes, coyotes, wolves, and raccoons. The virus is shed in feces and resists drying, heat, and cold, so it stays in the environment for a long time.
Dogs are infected by ingesting even a tiny amount of feces that contains parvovirus. Dogs can be infected by contact with an infected dog or with contaminated feces, surfaces, or objects. People who have handled infected dogs or contaminated objects can carry the virus on their hands or clothes and infect other dogs. Wild animals might be a source of environmental spread of parvovirus. Animals that have no symptoms can be carriers.
Effects on the Body and Signs of Infection
Canine parvovirus targets the lining of the small intestine, bone marrow, heart, and other organs. Destruction of the intestinal lining causes vomiting, bloody diarrhea, dehydration, loss of barrier protection against bacteria, and inability to absorb nutrients. Some infected animals develop intussusception, a potentially life-threatening condition in which a section of intestine folds into itself like a telescope. White blood cells (part of the immune system) are produced in the bone marrow, so infected animals have low white blood cell counts and impaired immune function. Because of decreased intestinal barrier protection and immune function, infected animals are at risk of septic shock caused by bacterial infection. Young puppies sometimes develop myocarditis, or inflammation of the heart muscle.
These are some of the signs of parvovirus infection:
Death can occur within 3 days after symptoms begin.
Parvovirus infection is often suspected on the basis of the patient’s symptoms, age, and vaccination history. Tests of fecal samples confirm the infection. A rapid test at a veterinary clinic is convenient but sometimes returns a false result, which can delay the diagnosis (this was the case with the outbreak in Michigan). A polymerase chain reaction (PCR) test at a diagnostic laboratory is accurate but takes longer. A blood test showing a low white blood cell count supports a diagnosis of parvovirus, especially in a sick puppy still awaiting a PCR test result.
Dogs with parvovirus infection usually also receive other tests, such as x-ray imaging or ultrasound of the belly.
For most dogs with parvovirus infection, the best chance for recovery is hospitalization for intensive care very soon after symptoms start. No antiviral drug that kills parvovirus is currently available, so treatment consists of measures to reverse dehydration, minimize vomiting and diarrhea, prevent bacterial infection, reduce pain, and restore nutrition. Intensive care for parvovirus infection can be expensive.
Most dogs that receive prompt intensive treatment in the hospital survive. Most dogs that are not treated die. For dogs whose owners can’t afford hospitalization, the success of outpatient treatment depends on the individual dog (illness severity and immune status), type of treatment, and ability of the owners to provide care at home.
The parvovirus vaccine is effective and is one of the core vaccines recommended for all dogs. This vaccine is part of the initial series of puppy vaccines. Puppies need to receive the entire initial vaccine series to have the best chance of being protected. The current recommendation is for puppies to be vaccinated every 2 to 4 weeks from the ages of about 6 weeks to at least 16 weeks. The vaccine is given again 1 year later and then every 3 years throughout the dog’s life. Some dogs never mount an immune response to vaccination (this is not common). Vaccinating all dogs helps keep puppies and vulnerable adult dogs safe.
Limiting a puppy’s exposure to other dogs and to places where other dogs gather reduces the risk of infection. However, this approach can hinder a puppy’s social and emotional development. In general, puppy classes and establishments that have protocols to reduce disease transmission (like requiring vaccines, proper disinfection and hygiene, and isolation of sick dogs) are relatively safe, especially when weighed against the risk of behavior problems in puppies that are not socialized. Exposure to dogs of unknown vaccination and health status, as in dog parks, is riskier. Ask your veterinarian about safe activities for your puppy, and keep your puppy away from sick dogs and other dogs’ feces.
For More Information
Public domain photo by C. E. Price
Laurie Anne Walden, DVM
Monkeypox is a zoonotic disease; it spreads between animals and humans. In the United States, the chance that a person will catch monkeypox from a pet or give monkeypox to a pet is very low. Transmission between people and pets is possible, though, so the Centers for Disease Control and Prevention (CDC) has developed monkeypox guidance for pet owners.
This article summarizes information from the CDC and the American Veterinary Medical Association (AVMA) and is current as of August 24, 2022. See these links for updates:
How Monkeypox Spreads
Monkeypox was first discovered in 1958 in monkeys and since then has been found in many animal species. Rodents and other small mammals (not monkeys) are thought to be the reservoir species that maintain the virus.
Human infection was first reported in 1970 in Africa, and monkeypox has occasionally appeared in other parts of the world. The United States had an outbreak in 2003 after pet prairie dogs were housed with infected animals from Ghana. The 2022 global monkeypox outbreak has involved at least 75 countries.
The monkeypox virus is related to the virus that causes smallpox. The virus infects the host through the respiratory tract, mouth, eyes, or broken skin. These are some of the ways people and animals are infected:
Most transmission during the 2022 outbreak has been through close, direct contact with an infected person.
Animals at Risk
One pet dog has contracted monkeypox, most likely from direct contact with its owners (this was the first reported case of human-to-animal transmission). Chinchillas, prairie dogs, and some types of rabbits, mice, and rats can be infected with the monkeypox virus. Many wild mammals are also susceptible to infection. Cats, guinea pigs, hamsters, and cows can be infected with other viruses in the same genus as monkeypox, but whether they can also be infected with the monkeypox virus is not yet known. The CDC says that it’s best to assume that any mammal can be infected. There have been no reports of infection in animals that are not mammals.
Signs of Monkeypox in Animals
These are some of the signs that infected animals have developed:
These symptoms are nonspecific. Many conditions that are much more common than monkeypox cause the same symptoms in animals. Diagnosing monkeypox requires laboratory tests.
Precautions for Pet Owners: CDC Guidance
If You Think Your Pet Has Monkeypox: CDC Guidance
Monkeypox. American Veterinary Medical Association. Accessed August 24, 2022. https://www.avma.org/resources-tools/one-health/veterinarians-and-public-health/monkeypox
Monkeypox in animals. Centers for Disease Control and Prevention. Updated August 17, 2022. Accessed August 24, 2022. https://www.cdc.gov/poxvirus/monkeypox/veterinarian/monkeypox-in-animals.html
Monkeypox: pets in the home. Centers for Disease Control and Prevention. Updated August 17, 2022. Accessed August 24, 2022. https://www.cdc.gov/poxvirus/monkeypox/specific-settings/pets-in-homes.html
Seang S, Burrel S, Todesco E, et al. Evidence of human-to-dog transmission of monkeypox virus. Lancet. 2022:S0140-6736(22)01487-8. doi:10.1016/S0140-6736(22)01487-8
Image source: CDC
Laurie Anne Walden, DVM
Urinalysis is part of the diagnostic workup for many medical conditions, such as kidney disease, diabetes, and urinary tract infection. Pets that are urinating in unfortunate locations need urinalysis because inappropriate urination can be a symptom of a medical problem. Routine wellness checks, especially for senior animals, often include urinalysis. Urine is also collected for bacterial culture and other tests.
Urinalysis includes measurement of urine concentration, chemical analysis, and examination under a microscope. The results are affected by the age of the urine and the way the sample is collected. Urine begins to change soon after it’s voided, so urine samples need to be very fresh, ideally delivered to the veterinary clinic within an hour. The collection container needs to be completely clean, with no residue from food or cleaning solutions that can affect the chemical test results. Debris in a urine sample interferes with the chemical analysis and microscopic examination.
Urine can be collected either at home or at the veterinary clinic, depending on the reason the sample is needed and individual pet and household factors (such as the animal’s temperament and medical conditions, owner’s ability to collect urine, and distance to the clinic). Home urine collection is fine for most routine urinalysis, but check with your veterinarian to be sure it’s appropriate for your pet. Sometimes urine needs to be collected in a sterile manner at the veterinary clinic. In these cases, urine is usually collected by cystocentesis, a technique using a needle inserted directly into the bladder.
General Urine Collection Tips
Collecting Urine From Dogs
Collecting Urine From Cats
Photo by Tran Mau Tri Tam on Unsplash
Laurie Anne Walden, DVM
Pets need stool tests to screen for parasites or help find the cause of diarrhea and other digestive system problems. Collecting a stool sample at home is the least stressful option for the pet. The alternative is for someone at the veterinary clinic to use a loop to remove a little bit of stool from the rectum. This option yields a much smaller sample and can be unpleasant for the animal.
A fecal test for parasites involves mixing the stool sample in a flotation solution and either spinning it in a centrifuge or leaving it to sit in a vial for a certain amount of time. The material at the top of the solution is then removed to a microscope slide to look for parasite eggs that have floated to the surface. Sometimes a tiny bit of stool is smeared directly onto a microscope slide for examination. Fecal analysis can also include chemical tests. For all of these tests, the stool needs to be fresh and squishy enough to mix or smear.
The age and condition of a stool sample affect the results. Parasite eggs can dry out or hatch in old stool. Hard, dry feces is very difficult or impossible to prepare for testing. Stool that has been sitting outdoors for a while can contain fly eggs or larvae (maggots). Liquid diarrhea that’s soaked into paper or cloth can’t be mixed in solution to test for parasites.
Here’s how to collect a stool sample to get the most accurate results:
Photo by Lucas Ludwig on Unsplash
Laurie Anne Walden, DVM
Lyme disease is the most common tick-borne disease in humans in the United States. Dogs can be infected with the bacteria that cause Lyme disease but are much less likely than people to develop symptoms.
Lyme disease is caused by infection with Borrelia burgdorferi bacteria, which are transmitted through tick bites. The tick responsible for infection in the eastern United States is Ixodes scapularis, the deer tick (also called the blacklegged tick). Deer ticks persist in the environment because they’re maintained in populations of deer and other wild animals. For this reason, Lyme disease is endemic—always present in the environment—in some parts of the country.
Deer ticks are smaller than American dog ticks and can be hard to see on animals with fur. The immature nymph stage, which can also transmit B burgdorferi, is tiny and even harder to spot.
Ticks live in woods, grassy areas, and underbrush. Ticks can’t jump or fly; they wait on the tip of a branch or grass blade until a person or animal brushes past, then they latch on. Adult deer ticks can be active when the weather is cool, so Lyme disease isn’t just a summertime risk.
Ticks transmit bacteria to the host animal while they’re taking a blood meal. It takes a day or two for B burgdorferi to pass from a tick into a host, so removing ticks within 24 hours reduces the risk of Lyme disease.
Humans and dogs don’t spread Lyme disease directly to each other, but dogs can bring ticks into the home. Infection in one host species also means that another host species living in the same environment is at risk. If a dog has a positive test for B burgdorferi, for example, that means the dog has been exposed to ticks carrying the bacteria, and people in the dog’s household are at risk for Lyme disease from the same ticks.
Most dogs (95%) infected with B burgdorferi don’t develop any symptoms. In dogs that become ill, symptoms start 2 to 5 months after infection and include fever, loss of appetite, and lameness that can shift from one leg to another. Some infected dogs develop kidney disease.
Cats can be infected with B burgdorferi, but whether they actually get sick from the infection is unknown.
Many dogs are routinely tested for B burgdorferi antibodies at the same time as their annual heartworm test. Antibody tests show whether a dog has been exposed to the bacteria. The American College of Veterinary Internal Medicine recommends yearly antibody tests for all dogs living in or near areas where Lyme disease is endemic. Dogs that test positive have further blood and urine tests to check kidney function and uncover other problems. A positive antibody test in a healthy dog also indicates a possible risk of Lyme disease for people living in the same environment.
Diagnosing Lyme disease in dogs with symptoms is not always straightforward. The same symptoms are caused by many different conditions. A positive antibody test means that at some point the dog was bitten by a tick carrying B burgdorferi, not necessarily that the infection is causing the current symptoms. A diagnosis is usually based on antibody test results (possibly more than 1 type of test), symptoms consistent with Lyme disease, lack of evidence of other causes of symptoms, and response to treatment.
Dogs with symptoms of Lyme disease are treated with antibiotics. Dogs that develop kidney disease need additional treatment.
Tick control is the best way to prevent Lyme disease. Many tick preventives are available for dogs; some are given by mouth and others are applied to the skin. Your veterinarian can suggest products best suited to your dog. Some products are available only by prescription.
The CDC website has lots of information about preventing tick bites in people and pets. See “Preventing Tick Bites” in the Lyme disease section of the CDC website: https://www.cdc.gov/lyme/prev/index.html
Vaccines for Lyme disease are available for dogs. Your veterinarian can advise you on whether you should consider having your dog vaccinated.
1. Lyme disease. Centers for Disease Control and Prevention. Accessed June 25, 2022. https://www.cdc.gov/lyme/index.html
2. Littman MP, Gerber B, Goldstein RE, Labato MA, Lappin MR, Moore GE. ACVIM consensus update on Lyme borreliosis in dogs and cats. J Vet Intern Med. 2018;32(3):887-903. doi:10.1111/jvim.15085
Ixodes scapularis image source: CDC
Laurie Anne Walden, DVM
Essential oils are compounds that give plants their scent and taste. They are volatile compounds, meaning that they evaporate quickly and release chemicals into the air. Essential oils are in many products: aromatherapy products, home fragrances, flavorings, personal care items (like shampoo), “natural” remedies, insect repellents, and so forth.
Essential oils can sometimes be dangerous for pets, so be aware of the possible risks if you use these products. Whether an essential oil will cause a problem for an animal depends on the type of exposure, the concentration of oil, the animal’s individual risk factors, and the type of oil.
The following essential oils are known to be toxic to cats and dogs, according to the Pet Poison Helpline.[1,2]
How Animals Are Exposed
Essential oils enter the body through the skin, by swallowing, or by inhalation. Pets are most often exposed to toxic levels when owners apply an essential oil directly to the skin or fur in an attempt to treat a skin condition or repel fleas. The oil is absorbed into the body through the skin, and the animal is further exposed by licking oil from the fur. The risk increases with higher concentrations of essential oils. Products containing a high percentage of essential oil (approaching 100%) should never be applied directly to an animal’s skin or hair.
Diffusers spread the fragrance of essential oils into a space. Passive diffusers work through evaporation: they send the scent of the oil, but not the oil itself, into the air. Passive diffusers are mainly a risk if a pet knocks one over and licks the oil or gets oil on the fur. Active diffusers (like nebulizers and ultrasonic diffusers) send actual particles of oil into the air. Oil from active diffusers can get onto an animal’s skin or be inhaled into the lungs, so the animal can have direct exposure to the oil without touching the diffuser. Strong odors from either type of diffuser can cause respiratory tract irritation.
Animals at Risk
Cats are at higher risk from essential oils than dogs are. Cats lack a liver enzyme that helps eliminate essential oils from the body. Cats and other animals that groom themselves are also more likely to swallow oil that’s collected on the fur.
Animals with asthma or other respiratory problems are at higher risk than others from inhalation exposure from diffusers. Birds are very sensitive to respiratory irritants, so diffusers can also cause problems for them.
Depending on the type of oil and the amount of exposure, essential oil toxicity can cause vomiting, diarrhea, drooling, tremors, loss of balance, skin irritation, coughing, difficulty breathing, low heart rate, low body temperature, rear leg paralysis, and liver failure.
Animals with symptoms of essential oil poisoning need veterinary care and might need to be hospitalized for intensive care.
Using Essential Oils Safely
Use essential oils with caution if you have pets. These tips can help keep your pets safe:
1. Benson K. Essential oils and cats. Pet Poison Helpline. Accessed June 4, 2022. https://www.petpoisonhelpline.com/blog/essential-oils-cats/
2. Marshall J. Essential oils and dogs. Pet Poison Helpline. Accessed June 4, 2022. https://www.petpoisonhelpline.com/pet-safety-tips/essential-oils-dogs/
Photo by Kadarius Seegars on Unsplash
Laurie Anne Walden, DVM
The contents of this blog are for information only and should not substitute for advice from a veterinarian who has examined the animal. All blog content is copyrighted by Mallard Creek Animal Hospital and may not be copied, reproduced, transmitted, or distributed without permission.