Category Archives: Poisonous Plants

You Make The Diagnosis: Cats And Flowers

Pictured below is a magnificent arrangement of flowers.  Although the flowers are beautiful, one type is highly toxic to cats.  Which flower is poisonous?  What are the symptoms of toxicity?

Diagnosis:  Lily  (Lilium and Hemerocallis species)

Lilies from the Lilium and Hemerocallis species contain a toxin that causes renal diease in cats.  (The two orange flowers with brown spots on their long, broad petals.)  Initially, affected individuals are anorexic and listless.  As their condition worsens, vomiting and diarrhea often develop.  Without treatment, most will develop renal failure in one to three days.  If you think your pet got into a lily, even the pollen, get veterinary help immediately.  With early diagnosis and aggressive treatment, most cats will recover from lily toxicity.    

Brutlag, Ahna.  From the Planter to the Carpet:  Toxic Plants and the Small Animal Patient. Western Veterinary Conference 2010. 

Oleander – The Entire Plant Is Poisonous

As a child, I remember my dad trimming the oleander bushes at my grandparent’s house.  The sap dripped on to his arms and caused painful rashes.  I did not understand how truly poisonous these plants were until years later when I entered veterinary school.  We were lucky that none of our pets consumed this pretty but deadly plant. 

Oleander contains a cardiac glycoside that is extremely toxic.  Just a few leaves will kill a dog.  After ingestion, the victim experiences vomiting or it will cause colic in species that do not vomit.  It also leads to diarrhea.  A short time later, the patient’s heart rate drops and arrhythmias begin.  All parts of the plant contain the toxin so extreme care must be taken to insure clippings are not mixed into fodder for ruminants or horses.  Since it is toxic to so many species (rabbits, camels, horses, chickens, cattle, llamas, alpacas, dogs, cats, humans), I would assume it is toxic to all creatures until proven otherwise.

If your pet or child is exposed to oleander or any of the other plants that also contain cardiac glycosides (lily-of-the-valley, foxglove, squill and some milkweeds) seek medical attention immediately.  Do not wait until clinical signs develop.  With proper care, most patients will make a complete recovery without any long term affects to their hearts or gastrointestinal systems.

   

Oleander comes in a variety of colors including red, pink and white.  Please use caution when working around these deadly beauties.

Lantana, A Beautiful But Poisonous Plant

Here in Arizona, many people use Lantana as a decorative plant in their yards.  The groundcover thrives in the high temperatures found in the Valley of the Sun.  They also grow in tropical regions.  In my neighborhood, I see them in gold, yellow, red and gold, purple, pink and yellow, and white. 
  
                                           

Unfortunately, the plant contains triterpenoid toxins that harm the liver.  The most common signs in dogs is vomiting and diarrhea.  If enough of the plant is consumed, some will die quickly.  This differs from grazing animals which usually die several weeks later due to a damaged liver.  Ruminants, rabbits, guinea pigs and female rats are all susceptible to this plant.  The red and yellow plants are the most toxic while the white is the least dangerous.  

If you have these plants in your yard, I may have to suggest removing them, fencing them off or using a basket muzzle on your dog to prevent exposure.    

Reference:
Sharma, Om P., et al “A review of the hepatotoxic plant Lantanta Camara” Crit Rev Toxicol, may 2007;37(4):313-52.

Texas Mountain Laurel Is Toxic To Animals

                                    

The Texas Mountain Laurel is a popular plant because of its purple flowers and artificial grape smell.  Unfortunately, the entire plant is toxic to animals.  The plant contains grayanotoxin, a toxin that binds to sodium channels in cell membranes and changes the permeability.  It affects the nervous system as well as skeletal and cardiac muscle.  Common symptoms of poison ingestion include vomiting, diarrhea, profuse salivation,  weakness, impaired vision and a slow heart rate.  Please seek veterinary care for livestock or pets that come into contact with this plant immediately.  This plant is very toxic.  Don’t let the beautiful flowers and sweet smell fool you.   

Reference:
Puschner, B. “Intoxication With cardiotoxic Plants” ACVIM 2007,

 

Grapes And Raisins May Cause Renal Failure In Dogs And Cats

Many of the foods humans enjoy are not good for pets and some are quite harmful.  Raisins and grapes are in this category.  Although the toxic principle has not been identified, it appears that the flesh of raisins and grapes contains a poison that causes renal failure in dogs and cats.  After ingestion, the animal develops high blood calcium levels that leads to acute renal failure.  Once renal failure develops, the prognosis is poor even with therapy.

If your pet ingests grapes or raisins, seek veterinary care immediately.  Although not all dogs are susceptible, I always ere on the cautious side and place the patient on intravenous fluids to protect the kidneys.  If the patient’s blood analysis looks good after two days of therapy, I breathe a (still cautious) sigh of relief.  

I never used to worry about this toxicity in cats, because I never thought a cat would eat a grape or a raisin.  Well, I was wrong.  I now know of at least one cat who ate raisins and became ill.  Please keep grapes and raisins in a secure location to prevent any accidents from occurring.  A special note for dachshund owners, dachshunds seem to love grapes so please make sure they do not have access to them.
  
   

Sago Palms Are Poisonous To Animals

After seeing so many poisonous plants for sale at the local home improvement store, I decided to start a new category dealing with poisonous plants.  The number of poisonous plants used in landscaping and as indoor plants is absolutely staggering.  Before you bring any plant into your house, check to see if it is safe for pets and small children. 

Sago palms, also called cycad palms are very poisonous.  The seeds, fruit and base are loaded with cycasin, a toxin that causes liver failure.  Ingestion of just one seed may cause death in a dog.  Vomiting, abdominal pain, diarrhea, depression and neurologic signs develop within a few hours of ingestion.  Abnormalities in the blood work lag behind clinical signs by about 24 hours making it hard to diagnose.  Death occurs within hours to days depending upon the amount of poison ingested.   

In a study of 60 dogs with sago palm toxicosis, 95% of them developed liver failure and gastrointestinal problems.  Neurologic signs including posterior paresis, depression, problems with coordination called ataxia and seizures occurred in 50% of the animals studied.  Unfortunately, once clinical signs occur, one third of dogs will die. 

If your pet has been exposed to a sago palm, bring them to your veterinarian for immediate decontamination.  Do not take a wait and see approach with this poison.  If you have these plants in your yard or house, I must suggest you remove them immediately to prevent an accidental poisoning.  The following pictures will help you identify this plant.

            

Reference:
Albretson, JC, et al, “Cycad palm toxicosis in dogs – 60 cases (1982-1997)”, JAVMA 1998 Vol 213 (1) pp. 99-101.