The well-known garden geranium belongs to a large genus of flowering plants called Pelargonium. There are more than 200 species of Pelargonium, comprising perennials, shrubs, succulents, and those grown as a garden annual. These plants are native to tropical and warm temperate regions, especially Southern Africa, so the leaves will die quickly at the first hard frost. Pelargonium species belong to the Geraniaceae family. They are mildly toxic due to several components found throughout the plant.

Geraniol is a pungent chemical that is a primary ingredient in essential oils like citronella and rose oil. It is a skin irritant and can be harmful to the eyes. The other toxic component, linalool, is a terpene chemical that can cause eczema and allergic reactions. Both these chemicals are only found in low levels in geraniums, however ingestion of any part of the plant can cause vomiting, reduced appetite, and depression in dogs. Skin contact with the leaves or broken stems may result in redness and irritation. Most dogs will avoid the plants for this reason, but puppies or dogs that are prone to eating house or garden plants could be more at risk. Adverse effects from geraniums are typically mild; individual sensitivity could make the symptoms more severe in some animals.

Oil of geranium is an essential oil which concentrates the more toxic elements of the plant, so exposure to this substance can be much more dangerous for animals. Pelargonium species of geranium should be distinguished from plants belonging to the Geranium genus, another member of the Geraniaceae family. These flowers are usually known as Cranesbills; they have five symmetrical petals, unlike Pelargonium species which have asymmetrical flowers with many petals. Cranesbills are hardier and less susceptible to frost; they are also non-toxic for pets.

The most common type of geranium found in gardens and flower pots is mildly toxic for dogs. Adverse reactions include dermatitis from skin exposure or vomiting after ingestion.

These are the symptoms you may see if your dog ingests or comes into contact with Pelargonium species of geranium:

These are some types of geranium your dog could be exposed to.

Pelargonium genus (sub-genera include Magnipetala, Parvulipetala, Paucisignata, and Pelargonium) – numerous species varieties including zonal and ivy-leaved geraniums. Does not survive frost well, but it is commonly used as a potted plant. The flowers are asymmetrical and come in a huge variety of colors. The leaves are typically stiff with scalloped edges and a darker colored rim. All parts of the plant contain toxic chemicals in low levels.

Geranium species (Cranesbill) – low growing plants with spreading stems that make good ground cover. Much more hardy than Pelargonium species. Many different varieties with pink, blue, purple, or white flowers that have five symmetrical petals. Non-toxic for pets.

Oil of Geranium (essential oil) – a concentrated essence of pelargonium species which could be very toxic to dogs.

These factors will increase the risk of geranium poisoning in your dog:

Geranium poisoning will be diagnosed based on symptoms and a history of exposure. Skin irritation and dermatitis are the most common symptoms if dogs brush up against the leaves. Oral irritation will usually prevent dogs from eating the plant, but if they do, vomiting and general depression may be present. 

It’s a good idea to contact a veterinarian any time your pet ingests a non-food plant. Be prepared to describe the species of geranium, as well as the size and weight of your dog, and how much you think was ingested. Some dogs can have little or no reaction to mild exposure, however, severe vomiting should always be treated by a veterinarian. 

If symptoms are extreme or you can’t identify the plant your dog has eaten, get immediate help either from an emergency veterinary service or a poison helpline. Essential oils are highly toxic for animals, so exposure to geranium in this form should also be treated as an emergency.

Many cases of geranium poisoning related to the plant don’t require treatment, but this will depend on how much was ingested and your dog’s reaction. You should gently clean any area of skin that has been topically exposed, including mouth and lips. If your dog has ingested any part of the plant, remove the un-swallowed material from his mouth and give water to drink. Don’t induce vomiting unless recommended by a professional.

Veterinary treatment could be necessary in severe cases. The veterinarian may induce vomiting if a large amount was ingested. Activated charcoal is also given to reduce the absorption of toxins in the gastrointestinal tract. Cathartic medication can be helpful in moving the toxins through your dog’s system faster.

Severe symptoms may need supportive treatment. Anti-emetics can help to stop chronic vomiting, and other medication may be used to coat the stomach lining and decrease gastrointestinal irritation. Topical ointments and anti-inflammatories can reduce dermatitis or allergic skin reactions. Dogs that are severely dehydrated from chronic vomiting may need supplemental fluids and electrolytes. This is rare with ingestion of the geranium plant, but exposure to the essential oil could require more aggressive treatment.

Many dog owners keep geranium plants in their house or garden without a problem. Dogs typically recover from mild exposure and may learn to avoid the plant due to the irritation caused by the leaves. Some dogs are more prone to eating plants than others and individual sensitivity or allergies may make your dog more susceptible. If this is the case, it’s best to stick with non-toxic Cranesbill species in your garden. Ask your veterinarian for advice on houseplants that won’t cause adverse reactions in your dog.