10 Indoor Plants that are Poisonous and Dangerous

10 Indoor Plants that are Poisonous and Dangerous

10 indoor plants that are poisonous and dangerous feat

Houseplants are a common element in home décor. Beautiful indoor plants add visual interest and greenery to your home interior, aid in purifying the indoor air and may offer medicinal benefits, too.

But this does not mean you can decorate with just any beautiful plant.

Many indoor plants are highly toxic in nature. Such plants can be dangerous for small children and pets, as well as some elderly people.

While some plants are toxic when ingested, some can cause an allergic reaction if you touch the stem or leaves or if your skin comes in contact with the sap or juice.


As most garden centers don’t provide warning labels on potted plants, buyers need to do their own research. This article will help you learn which plants pose the biggest threat to the more vulnerable members of your family.

indoor houseplants that are dangerousindoor houseplants that are dangerous

Here are the top 10 indoor plants that are dangerous.

1. Philodendron


Philodendrons are among the most popular houseplants because they are easy to grow and require little maintenance.

However, these plants contain insoluble crystals of calcium oxalate called raphites, which are the toxic element that makes them potentially dangerous.


While the calcium oxalate crystals usually have a very mild effect on humans, some people may be very sensitive to them. Contact with the plant’s sap may result in a burning sensation in the skin, irritation, and swelling of the lips as well as tongue.

Calcium oxalate is also toxic to pets, such as cats and dogs. Upon ingestion, it may cause possible symptoms including increased salivation, swelling of the tongue, vomiting, convulsions, decreased alertness, breathing problems and difficulty swallowing food.

If you have one of these plants in your home and your pet is showing some of these symptoms, wipe off the affected body part with a cold, wet cloth. Make sure to clean off any visible plant sap from the skin.

If you want to keep your philodendron plant, keep it in a high place that is out of reach of children or pets. Also, make sure to keep the tendrils and leaves trimmed.

2. Dieffenbachia



The dieffenbachia, also called dumb cane, is a beautiful houseplant with large, colorful leaves that definitely adds beauty to any home interior. But you must be aware of the fact that this indoor plant can present a danger to kids and pets.

Its leaves, stalk and roots are highly toxic in nature. The cells of the dieffenbachia plant contain needle-shaped calcium oxalate crystals that are highly toxic. Another toxic compound found in this plant is a protein called asparagine.

Both children and pets are vulnerable to this toxic houseplant.

When the leaves are chewed, calcium oxalate crystals can cause a host of symptoms, including intense numbing, oral irritation, excessive drooling and localized swelling. In rare cases, it can even cause difficulty breathing and swallowing.

3. Oleander



Oleander is a beautiful flowering shrub that can be grown indoors as well as outdoors. But, all parts of this plant are poisonous for both humans and pets.

It contains compounds called glycosides which cause symptoms like irregular heartbeat, excess salivation, sweating, oral irritation, nausea, vomiting, diarrhea, congested mucus membranes, shallow breathing, incoordination, and even death from cardiac failure.

Its milky latex can be irritating to the skin. In fact, it is best to wear gloves when handling the plant for extended periods.

If you have small children and pets in your home, keep this plant out of reach. Also, make sure to dispose of the trimmings and prunings of this plant carefully. Do not burn them as the smoke produces can be toxic.

This plant is not recommended for homes with cats.

4. Golden Pothos

golden pothosgolden pothos

The golden pothos, commonly known as devil’s ivy, is another indoor plant that is dangerous to pets. The American Society for the Prevention of Cruelty to Animals (ASPCA) has listed this houseplant as toxic to both cats and dogs.

Both the stem and leaves contain insoluble calcium oxalates, which upon chewing or biting can be harmful to cats and dogs.

Calcium oxalates cause tissue irritation and possible swelling of the lips, tongue, oral cavity and upper airway when chewed. If the swelling is severe, pets may even shows signs of difficulty breathing or swallowing. Other clinical signs of toxicity include pawing at the face, drooling, foaming, lack of appetite and vomiting.

Proper care should be taken to ensure the plant is not consumed by pets. Plus, this plant can be toxic to children as well.

5. Arrowhead Plant

arrowhead plantarrowhead plant

This lovely houseplant with long, heart-shaped leaves looks extremely beautiful and gives a nice touch to any home décor. Due to its sheer beauty and easy maintenance, people across the globe love to keep this houseplant in their homes, without even knowing about its toxic nature.

Both humans and animals are vulnerable to its toxic nature. The juice or sap of this plant contains oxalate crystals, which are highly toxic.

Coming in contact with the sap or the leaves can lead to irritated skin, swelling and a burning irritation in the mouth, throat and stomach.

When dogs and cats ingest the leaves, they may exhibit excessive drooling, pawing at the mouth, difficulty swallowing, swelling of the mouth and even vomiting.

As the plant grows very quickly and the leaves shed often, you must check for fallen leaves and discard them as soon as possible.

6. Peace Lily

peace lilypeace lily

The peace lily, also known as the Mauna Loa plant, is another beautiful and popular houseplant that falls in the dangerous category.

This houseplant contains insoluble calcium oxalate crystals in bundles known as raphites, which are toxic to cats and dogs. These crystals get released upon chewing or biting the leaves, stems or roots and penetrate the pet’s tissue leading to injury.

When a pet ingests the toxic elements of this plant, it can cause symptoms including pawing at the face, oral pain, drooling, foaming and vomiting. Moderate to severe swelling of the lips, tongue, oral cavity and upper airway can also occur. It can also cause dehydration and the possibility of renal failure, which is a severe condition in pets.

It is also poisonous to humans due to the alkaloid lycorine, which is present in the bulbs and stems. In humans, this toxic plant can cause swelling of the lips, mouth and tongue, nausea, vomiting, diarrhea and difficulty swallowing.

7. Crown-of-Thorns

crown-of-thorns plantcrown-of-thorns plant

Euphorbias and spurges like the crown-of-thorns are toxic to humans as well as pets. All parts of this plant are poisonous and may cause stomach and mouth irritation upon ingestion with symptoms like excess salivation, swelling about the eyes and mouth, stomach pain, nausea, vomiting and diarrhea.

Contact with skin may cause redness, swelling and blisters.

The toxic element in this houseplant is diterpene esters, which are present in the milky sap found in the veins of the plant.

Poinsettia, the traditional Christmas flowering plant, also belongs to Spurge family. Like other spurges, it is also considered poisonous. However, it is not as toxic and poisonous as other Euphorbias and spurges.

8. Caladium


When grown in an indoor location, the beautiful, decorative caladium surely becomes the prime attraction of the room. This bulb plant with long-lasting foliage is easy to grow and needs little maintenance. However, this potted plant can be toxic to both humans and animals.

This plant is highly toxic to dogs as well as cats, due to the toxic insoluble calcium oxalates in it. Another toxic ingredient is asparagine, a protein found in the plant’s leaves.

All parts of the plants are poisonous, particularly if large amounts are ingested.

Signs of toxicity after ingestion are intense burning and irritation of the mouth, tongue and lips, excessive drooling, diarrhea, a hoarse voice, vomiting and difficulty swallowing. It may even cause blistering in the mouth, which may prevent normal speaking and swallowing. If ingested in high amounts, it may even cause problems as severe as coma or death.

In case of skin irritation, it is important to rinse the affected area thoroughly with lukewarm water if signs of toxicity appear.

9. Elephant Ear

elephant earelephant ear

Elephant ear plants with very large, arrow-shaped leaves add a nice green touch in nearly any interior setting. People love this houseplant for the large, tropical-looking foliage, which is reminiscent of elephant ears.

Plus, growing and maintenance of elephant ear plants is easy.

Keeping beauty aside, very few people are aware of the fact that this houseplant is dangerous.

Poisoning may occur if you ingest parts of this plant due to the harmful substances in it, such as oxalic acid and asparagine (a kind of protein). The leaves and stems are the most toxic parts of the elephant ear plant.

Ingestion can cause symptoms like diarrhea, nausea, vomiting, and burning and swelling in the mouth, throat or eyes.

If your child or pet ingests the leaves, consult your doctor or vet immediately.

10. Asparagus Fern

asparagus fernasparagus fern

The asparagus fern is another very common houseplant, loved for its fine, feathery foliage. The foliage is used in floral arrangements, also. However, this toxic plant is dangerous, especially if you have a cat or dog in your house.

According to the ASPCA, both the leaves and berries of the plant contain chemicals that are toxic to cats. The toxic element is sapogenin that contains steroid compounds.

If a cat or dog ingests the berries of this plant, it can result in vomiting, diarrhea and abdominal pain. Also, external contact with the plant can be very harmful to your cat. It can cause severe skin irritation.

Whether you wish to keep this plant indoors or out, hang it out of reach of your cat. Also, remove the berries and trim the branches occasionally.


Though toxic in nature, the 10 indoor plants mentioned above are beautiful to look at. If you want, you can add these plants to your home décor as long as precautions are taken.

  • Always keep the plants on high shelves so they are out of reach of children and pets.
  • If you have a cat, put these plants in bird cages so that your cat cannot touch them.
  • Regularly sweep up any leaves that may fall from the plants. Wear gloves to prevent touching them with your bare hands.
  • Make your children aware of the inherent dangers of these toxic plants and teach them not to touch the plants.
  • Clearly label the pots of poisonous plants to ensure guests are safe.
  • Always wash your hands whenever handling these toxic plants.
  • Trim plants regularly to prevent children and pets from accessing vines.
  • Always keep fresh water accessible for pets to prevent them from drinking water from plant trays.
  • If using hanging pots, make sure they are sturdy enough to support the weight of the plant.





Leave a Reply