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22 PRACTICAL TOXICOLOGY PEER REVIEWED properties in the sap are the toxic principle and have a "soapy" effect on tissues. Dermal exposures in pets can cause pruritus, erythema, and irritation. Ocular exposure may lead to conjunctivitis. Ingestion irritates the mucosa, resulting in hypersalivation, vomiting, and possibly diarrhea. Clinical signs are expected to be mild and self-limiting, and frequently no medical treatment is required. Large ingestions can be diluted with milk and water. Owners should withhold food and water for several hours if vomiting occurs. The pet should be bathed with a mild shampoo and water if sap is on the coat. In cases of ocular exposure, flush eyes with saline or tepid tap water. Prognosis for full recovery is excellent. ROSEMARY (ROSMARINUS OFFICINALIS ) Rosemary is known as the herb of love and remembrance. A small evergreen shrub, it has a rich, pungent flavor and a pleasant aroma. Although exposure to rosemary occurs year round, rosemary is often trimmed into a pine tree shape for a miniature Christmas tree. Rosemary contains a variety of volatile essential oils. In small quantities (such as the amount used in cooking), no toxic effects are seen. However, large ingestions of extracts or oils can result in gastrointestinal upset and irritation, as well as renal and neurologic effects. The mechanism of toxicity is not well understood. Gastrointestinal signs are most likely due to a direct irritant effect. The hypotensive effects are due to the spasmolytic action on smooth and cardiac muscles. Finally, the convulsant effect is theorized to be caused by monoterpene ketones. Reproductive effects are possible but rarely a concern in dogs and cats. Small to moderate ingestions may cause nausea and vomiting, as well as diarrhea. Large ingestions, in addition to gastrointestinal signs, may cause hypotension, weakness, pale mucous membranes, depression, acute kidney injury, and seizures (humans). Seizures are most likely due to monoterpene ketones. 7 Most cases causing significant clinical signs involve concentrated oils and extracts. Ingestion of the plant typically causes only mild gastrointestinal upset, which can be managed by a pet owner at home by withholding food and water for 1 to 2 hours. If vomiting and diarrhea worsen, the animal should be transported to the veterinarian. In cases of large ingestion, induce emesis. Antiemetics, fluid therapy, and pressor agents (drugs that raise the arterial blood pressure, such as epinephrine or norepinephrine) should be used in cases of hypotension. Obtain a complete blood count and chemistry profile and manage seizures if needed. STAR-OF-BETHLEHEM (ORNITHOGALUM SPECIES) Star-of-Bethlehem is a perennial plant that grows from a bulb. Most plants are grown outdoors, although some dwarf varieties are potted. Because of the star-shaped petals, this plant is frequently included in bouquets around the Christmas holidays. All parts of the plant are toxic, although the toxins are concentrated in the bulb. This plant contains 2 alkaloids: convallatoxin and convalloside. These are cardiac glycosides. Clinical signs and treatment are similar to those for kalanchoe ingestion. Pets generally have access only to the foliage, and most ingestions of cut flowers result in mild clinical signs. SUMMARY Although pets are more likely to be exposed to these plants at Christmas, ingestions are unlikely to cause serious, life-threatening signs. Most cases can be managed at home. Advise clients to gift pet-safe bouquets and houseplants to friends and family members who have pets. Some common safe houseplants include African violets and orchids. Suggestions for cut flowers include roses, Alstroemeria species (Peruvian or Brazilian lily), Gerbera daisies (Gerbera jamesonii), snapdragons, and sunflowers. Charlotte Means Charlotte Means, DVM, MLIS, DABVT, DABT, is Director of Toxicology at the ASPCA Animal Poison Control Center (APCC). She received her DVM and undergraduate degree from Oklahoma State University and a master's degree in library and information science from University of Oklahoma. Dr. Means worked in small animal practice and as a clinical medical librarian before joining the ASPCA APCC. PRACTICAL TOXICOLOGY continued on page 28