© Shutterstock 

Sago palm -

Sago palm contains a toxin called cycasin, which is known to cause liver damage. The whole plant (and in particular the seeds) poses a danger to pets if bitten or chewed. Symptoms of ingestion include vomiting, increased thirst, hemorrhagic gastroenteritis, bruising, clotting disorder, liver damage, liver failure, and, in extreme cases, death.

© Shutterstock 

Aloe vera -

Aloes are toxic to dogs but only when they ingest the pulp and the juice of the plant. Symptoms include vomiting, depression, and diarrhea. A lack of appetite and change in the color of urine are other telltale signs.

© Shutterstock 

Jade -

Keep cats and dogs away from this plant. It is mildly poisonous, but the exact toxins it produces are unknown. However, ingesting any part of it will result in your pet experiencing nausea, and most likely vomiting.

© Shutterstock 

Flame lily -

Like most of the lily species, the flame lily poses considerable danger to your pet, and especially cats. The entire plant is crammed with a cocktail of colchicine-related alkaloids. Ingestion initially causes salivation, and then vomiting and diarrhea, both mixed with blood. Shock ensues, then kidney failure, liver damage, bone marrow suppression, paralysis, and eventual death. 

© Shutterstock 

Ivy -

Ivy is poisonous, and must not be ingested as it contains a bitter-tasting toxin called saponin. The entire plant poses a risk to dogs, with drooling, vomiting, diarrhea, and abdominal pain being among the penalties for snacking on a leaf.

© Shutterstock 

Gardenia -

Despite its pleasant bouquet, gardenia is mildly toxic (though some species do pack a more poisonous punch). As a rule, do not allow your dog or cat to nibble at its leaves. Ingested, the plant will induce nausea and diarrhea.

© Shutterstock 

Peace lily -

Cats and dogs are often quite partial to flowering plants, species like peace lilies. But beware. This plant contains calcium oxalates which can irritate your pet's mouth, lips, and tongue, and can cause other mildly distressing symptoms.

© Shutterstock 

Geranium -

This is one plant that cats and dogs generally keep away from. But don't get complacent. Its toxins—geraniol and linalool—can cause mild symptoms of vomiting, anorexia, and dermatitis.

© Shutterstock 

Begonia -

A wonderfully attractive plant, begonia is nonetheless mildly toxic to pets due to a high percentage of insoluble oxalates contained throughout the whole plant. If you suspect your dog or cat has inadvertently taken a nibble out of it, look out for excessive drooling, irritation in and around the mouth, and vomiting.

© Shutterstock 

Dieffenbachia -

Also known as dumb cane, any part of the plant can cause distress to cats and dogs due to the amount of insoluble calcium oxalates and proteolytic enzyme it contains. Symptoms to watch out for are excessive drooling, vomiting, and difficulty in swallowing. Your pet may also display irritation of the mouth, lips, and tongue.

© Shutterstock 

Philodendron -

Mildly toxic to pets if any part of it is ingested, the philodendron can cause problems such as drooling, irritation of the mouth, lips, and tongue, and perhaps even vomiting.

© Shutterstock 

Kaffir lily -

Ingestion of any part of the kaffir lily, but especially the base of the leaf, stem, and bulbs, can cause kidney failure in cats. Dogs are also affected by its toxins, which include licorine and other alkaloids. Vomiting and diarrhea are first indicators that something is wrong. Convulsions, low blood pressure, tremors, and cardiac arrhythmia will tell you the situation is more serious.

© Shutterstock 

Strelitzia reginae -

Also known as "bird of paradise flower," this plant is toxic to cats and dogs. Keep pets well away from all parts of the plant. Signs of ingestion include mild nausea, vomiting, drowsiness, difficulty in breathing, and loss of appetite. Note that this plant should not be confused with Caesalpinia or Poinciana gilliesii, which is known as "bird of paradise" and is more toxic.

© Shutterstock 

Alocasia -

The leaves, stems, and roots of the alocasia contain insoluble calcium oxalates that can cause your pet to experience discomfort of the mouth and induce excessive drooling, vomiting, and sometimes difficulty in swallowing.

© Shutterstock 

Golden pothos -

Also known as satin or silk pathos, the insoluble calcium oxalates contained in this plant serve as a mild irritant to both dogs and cats. Excessive drooling and difficulty in swallowing are indicators that your pet has mistakenly taken a bite out of a leaf.

© Shutterstock 

Ficus benjamina -

You'll know if your pet comes into contact with this plant. Exposed skin will become noticeably inflamed. If any of the plant is ingested, irritation of the mouth may occur. These symptoms are due to the proteolytic enzyme (ficin) and psoralen (ficusin) found in this particular plant species, which is also known as a weeping fig.

© Shutterstock 

Asparagus fern -

The foliage and berries are harmful parts of the asparagus fern. If ingested, the toxic sapogenins can cause a cat or dog to experience gastrointestinal problems allied with vomiting, diarrhea, and unpleasant abdominal pain.

© Shutterstock 

Cyclamen -

This flowering plant, also known as sowbread, will certainly brighten up your room. However, it contains irritating saponins, and when any part of the plant (especially the tubers or roots) are chewed or ingested by dogs and cats, it can result in clinical signs of drooling, vomiting, and diarrhea.

© Shutterstock 

ZZ plant -

All parts of the ZZ plant, known also as the Zanzibar gem, contain insoluble calcium oxalates. While the threat to your pet is fairly low, the plant can cause a mild burning sensation to the mouth. Other symptoms include excessive drooling.

© Shutterstock 

Desert rose -

Don't be fooled by its romantic name. This plant can harm your dog or cat. All parts of the desert rose are poisonous, including sap. The toxic compound is digoxin, which can cause vomiting, diarrhea, anorexia, depression, and irregular heartbeat. Death can occur if ingested in large quantities.

© Shutterstock 

Amaryllis -

Another member of the lily family but considerably less toxic than others lilies, amaryllis only poses a threat if the bulb is ingested. This may cause vomiting, a drop in blood pressure, abdominal pain, drooling, and a likely loss of appetite.

© Shutterstock 

Hawaiian ti plant -

Keep canines away from this plant! The saponin compound in the Hawaiian ti plant is dangerous to your dog. Side effects can range from mild to critical depending on the amount eaten and health of your pooch.

© Shutterstock 

Dracaena fragrans -

Commonly called the corn plant, ingesting any part of this plant can cause vomiting and a subsequent lack of appetite in your dog or cat. Other clinical signs include anorexia, hypersalivation, and dilated pupils (cats).

© Shutterstock 

Scheffler -

The calcium oxalate crystals found in this plant can cause discomfort if chewed. The generally mild symptoms include excessive drooling, vomiting, and difficulty in swallowing.

© Shutterstock 

Kalanchoe -

This plant contains a naturally occurring poison, a toxin called bufadienolide that affects the heart. The entire plant is harmful to pets, and if ingested will cause vomiting, diarrhea, and general gastrointestinal irritation or upset.

© Shutterstock 

Eucalyptus -

Dogs have a natural dislike for the smell of eucalyptus oil, which can trigger mood swings in your pet. Licking or chewing any part of the plant will cause salivation, possible vomiting and diarrhea, and depression in a canine. Cats, being curious, will investigate eucalyptus, but ingestion of the plant by felines can be dangerous.

© Shutterstock 

Flamingo flower -

Chomping on the flamingo flower will leave a bad taste in your pet's mouth. It contains insoluble calcium oxalates, and symptoms of ingesting any part of the flamingo flower can result in your pet experiencing mucous membrane irritation, and an intense burning sensation on and around the mouth, lips, and tongue. Difficulty swallowing is commonplace.

© Shutterstock 

Oleander -

Oleander is notorious for its cardiac glycosides, harmful toxins that can kill a dog or cat. The whole plant is potentially deadly and if ingested can cause colic, diarrhea, and sweating. In time your pet will experience difficulty with coordination, shortness of breath, difficulty in breathing, and muscle tremors. If not treated urgently, death can occur due to heart failure.

© Shutterstock 

Peyote -

A plant in the cactus family, peyote works well as an ornamental plant and even has medicinal properties. But it's poisonous for dogs. It contains mescaline and other alkaloids that if ingested can induce psychotropic, intoxication, vomiting, and diarrhea.

© Shutterstock 

Calla lily -

There's no doubting its beauty, but the calla lily is dangerous for dogs and cats. The plant contains insoluble calcium oxalates and unidentified, toxic alkaloids, the effects of which are immediate if ingested. Symptoms include oral discomfort, diarrhea, excessive drooling, lack of appetite, and telltale pawing at the mouth. 

Sources: (The American Society for the Prevention of Cruelty to Animals) (People's Dispensary for Sick Animals)

See also: How to protect your pets during winter.

© Shutterstock