Marigold Poisoning in Dogs

Marigolds are of the family Asteraceae and are pretty plants with bright flowers capable of adding beautiful hues of red, orange and yellow to your garden space. They come in different varieties and many colors, and can be grown indoors and outside. There is also a species of wild marigold slowly moving across the southern states, in both cultivated and wasteland spaces. Some species of marigold are not considered toxic. However, some branches of the family can cause stomach upset when eaten and contact dermatitis when touched.

Most cases of ingestion of the marigold will mean a mild episode of gastrointestinal upset. The skin irritation that may be experienced with exposure will typically be short lived as well. In instances where a dog consumes a large amount of the marigold plant (especially the species known for toxicity), the event could result in discomfort for your pet but is not considered to be lethal. Phototoxic thiophene derivatives are responsible for the skin irritation. Stomach distress results because your pet’s digestive system does not have the enzymes to properly break down greenery, leaves, and flowers.

The marigold plant can be mildly toxic to dogs when ingested and can also cause  irritation when contact is made with the fur and skin. Though the effects of this plant are not life-threatening in any way, your pet may experience discomfort with exposure.

When a pet ingests a potentially poisonous plant, it is always a good idea to see the veterinarian for an evaluation. Often, plants will cause only mild side effects but if a dog has an underlying disease process in tandem with the toxicity, more serious effects could arise. Ingestion of the marigold may result in the following signs after exposure.

• Vomiting
• Drooling
• Diarrhea
• Stomach pain
• Irritation around the eyes and nose
• Redness of the skin
• Irritation of mucous membranes

Types

Not all marigold plants produce the same toxicity. Common marigold plants seen in gardens and homes of North America are:

• Marigold (Calendula officinalis) is considered nontoxic but a large ingestion by a dog could result in digestive problems, and this plant is thought to promote uterine contractions in pregnant humans and animals when eaten
• Marigold (Tagetes spp., Tagetes erecta, Tagetes patula) are known to cause stomach upset and skin irritation
• Marigold (Tagetes minuta) is an invasive weed form of the plant that has sap irritating to the skin

• If a dog eats large amounts of the marigold, he may experience digestive issues that must be treated by a veterinarian
• The noxious sap found on marigolds of the Tagetes species can cause irritation to the eyes, nose, and mouth
• The skin irritation dissipates within several minutes
• Some types of marigold in the Calendula branch are edible, but a dog may graze to the extent that he has stomach pain and diarrhea

If you witness your dog ingesting a plant from the garden, you should call your veterinary clinic for advice. If you see that your pet has plant material in and around his mouth, evaluation by a veterinarian is recommended, particularly if you are not certain what type of plant was ingested or in what location your dog found it. One should always keep in mind that pesticides could have been used on gardens or greenery in your area or in parks you may frequent when walking your dog. The plant your dog sampled may not be toxic but the pesticide is. In addition, because canines do not have a digestive system that is designed to process foliage and flowers, an intestinal blockage could occur if your dog has problems passing the plant matter through his body. 

Bring a sample of the plant to the clinic; it is possible that the identification of the plant will be sufficient for diagnosis. Depending on the symptoms that your dog is exhibiting (such as vomiting or diarrhea), the veterinary team may order testing such as complete blood count, urinalysis, and fecal analysis in order to rule out disease processes that may have similar symptoms. The abdomen of your dog will be palpated to verify if there is a ball of plant matter that could become an obstruction. If there was exposure to sap from the marigold, the veterinarian will examine your dog’s fur and skin.

Most cases of exposure to marigold will result in very mild symptoms. The treatment will depend on how your pet is reacting to the ingestion of the plant. Other factors that may determine treatment are your dog’s age and his current health status. On occasion, aged or health compromised dogs may experience a toxicity that is more severe than a younger or healthier canine. For example, if there are preexisting kidney issues, compounds in the plant may exacerbate the condition, or the kidneys may have trouble eliminating the toxin.

If your dog is vomiting excessively, the veterinarian may administer intravenous therapy to balance electrolytes and provide fluids which will help the liver and kidneys flush the toxins from the body. Antiemetics can be given, as well as cathartic medication to help your pet pass the plant matter in a bowel movement. If your dog’s skin is irritated by the marigold sap the veterinary team will gently wash his fur and skin, paying attention to the eyes and mouth, and apply a soothing ointment afterward if needed.

Studies show that the marigold is considered mildly toxic unless a large amount of the plant and flower is eaten. The toxins within the plant may not cause a gastrointestinal or dermal reaction, but care should be taken to avoid letting your dog eat vegetation and flowers at will. Pet owners should be aware of the potential poisonous effects and the chance of an obstruction caused by the leaves, stems, and flowers of plants. If you have a dog who likes to graze on greenery, plant canine safe grasses in your garden so he can satisfy his palate there, rather than on unknown foliage.