Sweet William is known to the world of science by their scientific name, Dianthus caryophyllus and belongs to the Caryophyllaceae family of plants. To the rest of the world, the plant is commonly called carnation, wild carnations, and pinks. Carnations are identified by their bluish-grey to green colored leaves and fringed flowers that bloom in a pale to dark pink coloration. Species of the carnation can be found in Europe, Northern Africa and portions of North America. The plants usually blooms in late July to early August and seeds in September. 

Sweet William plants are only mildly toxic to felines, causing clinical signs of gastrointestinal upset such as vomiting and diarrhea. Sweet William plants, like other Dianthus species, contain triterpenoid saponins that cause dermatitis when the sap comes into contact with the skin. These saponins are also believed to cause a similar irritation to the esophagus, stomach, and lower digestive system when ingested. Although no reports have been made of a feline Sweet William poisoning fatality, the ingestion of this plant should always be taken seriously. 

Sweet William poisoning in cats will cause clinical signs of mild toxicity. The most common clinical sign is gastrointestinal upset such as vomiting and diarrhea. The feline may get sick one or more times, depending on the quantity of plant material he or she consumed. The act of vomiting and diarrhea often causes secondary symptoms of dehydration, weakness, as well as decreased appetite. The Sweet William plant also has a sap that is known to cause dermatitis-like symptoms. Therefore, the cat’s lips and mouth may be reddened, swollen or irritated in appearance. The symptoms associated with Sweet William poisoning in cats are usually short-lived, lasting only a few short hours. 

Sweet William poisoning in cats is caused by the ingestion of the stem, leaves, petals, pollen or seeds of the plant. The exact toxicity content of the Sweet William plant is unknown, but experts believe the steroidal saponins that all member of the Caryophyllaceae family contain to be the toxic component. Steroidal saponins are the glycoside of pentacyclic oleanane, known to cause a potentially serious intoxication in mammals. The saponins often cause dermatitis, an allergic reaction of the skin, when coming into contact with the plant’s sap. This same irritant is believed to be the source of gastrointestinal upset associated with ingestion of the carnation plant. 

Diagnosing sweet William poisoning in cats is difficult without the cat having been witnessed eating the plant, as there is no specific test available for identifying this type of toxicity. Diagnosis will depend on ruling out other possible causes of your feline’s condition. The diagnostic process will begin with a physical examination, review of the feline’s medical history, and a consultation with the pet owner. It will be important for you to inform the veterinarian about your cat’s recent actions and exposure to sweet William, or other possible sources of toxins. 

The veterinarian may request a variety of tests to help confirm a diagnosis: 

As sweet William poisoning is generally mild in felines, there is no true treatment specifically deemed for this type of poisoning in cats. The cat’s own body does a fairly adequate job of removing the toxin from the body through vomiting and passing the digested particles through waste. However, a feline may require veterinary attention to induce vomiting and replenish fluids. An emetic drug, or drug that encourages vomiting, paired with intravenous fluids may be administered to the feline upon veterinary visitation. A medication used to coat the stomach and prevent further irritation from the plant sap may also be given as part of the treatment regimen. 

Without further exposure to the sweet William plant, your feline will be able to make a full recovery in a few short hours. Your veterinarian will likely ask you to encourage the feline to consume a larger amount of water than usual to further eliminate the toxin from the body for the day of toxic intake, but activities should return to normal in a few hours. Always consult the veterinarian when your feline consumes a sweet William plant, as larger consumptions could result in a more serious end result.