Plants That Irritate

Mouth irritants

Oxalate plants contain sharp, tiny crystals in their juices, leaves and stems, called calcium oxalate crystals. Oxalate crystals can cause intense pain and swelling if they come in contact with the skin or mouth.

When any part of these plants is chewed and swallowed, the crystals stab the sensitive tissues of the tongue, gums and throat, creating the sensation of biting into ground glass. Pain, difficulty swallowing, swelling and temporary hoarseness may occur.

Poisoning from swallowing an oxalate-containing plant is rare because the intense mouth pain usually prevents children from eating a significant quantity of the plant.

If a child eats any part of an oxalate-containing plant, wipe out the residue of the plant from the mouth and offer a cool drink or snack such as a popsicle, applesauce or yogurt. If there is swelling that prevents the child taking anything by mouth or causes difficulty breathing, go to the nearest emergency department immediately.

When the juices of the plant come in contact with the skin, burning, pain and swelling may occur. Lather the exposed area repeatedly with soap and rinse with warm running water to ease the irritation. If the pain continues, contact your child's physician.

Examples of plants that contain oxalates include:

  • Caladium
  • Calla Lily
  • Devil's Ivy
  • Dieffenbachia (Dumb Cane)
  • Elephant's Ear
  • Jack-in-the-Pulpit
  • Mother-in-Law's Tongue
  • Philodendron
  • Rhubarb
  • Spathiphyllum (Peace Lily)

Gastrointestinal irritants

The juices, leaves, roots and seeds of plants containing gastrointestinal irritants can produce stomach cramps, nausea, vomiting and diarrhea. With most of these plants, vomiting and diarrhea are mild and should last only a few hours. Ingesting small quantities of these plants should not cause any symptoms. However, eating an amount comparable to the size of a small salad would be poisonous.

If your child eats one of these plants, wipe out the mouth and offer food or milk. If vomiting or diarrhea occurs, give plenty of clear liquids to prevent dehydration. If the symptoms are severe and/or prolonged, contact your child's physician.

Examples of gastrointestinal irritants include:

  • Aloe
  • Buckeye-Horse Chestnut
  • Carnation
  • Daffodil
  • Eucalyptus
  • Geranium
  • Hyacinth
  • Pokeweed
  • Pyracantha

Skin irritants

Contact with the leaves or sap of skin-irritant plants can cause a condition called dermatitis, characterized by rashes, hives, swelling and itching of the skin. There are several different types of dermatitis.

Poison ivy or poison oak cause allergic dermatitis. The body's allergic response to the plant toxins may not be apparent for several days and may involve the whole body, even the areas that were not exposed to the plant.

Most of the other plants cause chemical dermatitis; this is not an allergic response but a direct effect of the chemical contained in the plant. Symptoms of chemical dermatitis occur within 24 hours of exposure and are generally confined to the area of contact.

After contact with a skin irritant plant, wash the exposed areas thoroughly with soap and water. Use hydrocortisone cream to treat irritation and inflammation of the skin. Antihistamines may alleviate the itching and hives. The majority of allergic and chemical reactions will clear up in 14-21 days. However, if the symptoms persist or worsen, contact your physician for further treatment.

Examples of skin irritants include:

  • Chrysanthemums (Mums)
  • Marigold
  • Poinsettia
  • Poison Ivy, Poison Oak and Poison Sumac
  • Ruby Plant
  • Schefflera
  • Wandering Dude

Next Steps
Girl getting a hug from toddler sister.

What to Expect When You Call

When you call the Poison Control Center, we will ask you a series of questions. Here's what we'll need to know so we can help.

Boy smiling

Poisoning Resources for Professionals

Find treatment tips for poisoning events, clinical pathways, information about toxicology assessments, and more.