Poisonous Plants, Foods, Medications and Chemicals

Species-Specific High-Risk Toxins

• Cats — True lilies and daylilies (Lilium and Hemerocallis) can cause acute kidney failure from very small exposures, including pollen and vase water. Acetaminophen and concentrated permethrin dog products are also major feline hazards.
• Dogs — Xylitol, grapes/raisins, macadamia nuts, sago palms, rodenticides, NSAIDs and many human medications are especially important.
• Birds — Avocado can be highly dangerous to many bird species. Overheated PTFE/non-stick coatings and other fluoropolymer fumes can cause sudden respiratory death. Aerosols, smoke, essential oils and heavy metals are also important hazards.
• Horses — Red maple, black walnut shavings, yew, oleander, locoweed, blister beetles in alfalfa hay, and many range plants are important hazards.
• Rabbits and small mammals — Avocado, many toxic houseplants, lead and other heavy metals, medications, pesticides and unsafe human foods can be dangerous. Species-specific metabolism means dog/cat guidance cannot always be extrapolated.
• Reptiles and amphibians — Pesticides, insecticides, heavy metals, contaminated feeder insects, toxic plants/foods and inappropriate medications can be hazardous. Amphibians are particularly sensitive to chemicals absorbed through the skin.

Foods and Food-Related Toxins

• Alcohol and alcohol-containing products — Ethanol intoxication; also beware unbaked yeast dough, which can produce ethanol and expand in the stomach.
• Caffeine — Coffee, tea, energy products, caffeine tablets, some supplements and coffee grounds can cause methylxanthine toxicity.
• Chocolate and cocoa — Theobromine and caffeine; baking chocolate and cocoa powder are especially concentrated.
• Grapes and raisins — DOG EMERGENCY: can cause acute kidney injury; a reliably safe dose has not been established.
• Xylitol / birch sugar / wood sugar — DOG EMERGENCY: can cause profound hypoglycemia and, with larger exposures, acute liver injury. Found in some gums, candies, baked goods, oral-care products, medications and nut butters.
• Onions, garlic, chives, leeks and related Allium species — Can cause oxidative red-blood-cell injury, especially in cats and dogs; concentrated powders are important sources.
• Macadamia nuts — Dogs may develop weakness, tremors, vomiting and hyperthermia.
• Raw or unbaked yeast dough — Can expand in the stomach and generate ethanol.
• Moldy foods and compost — Tremorgenic mycotoxins may cause severe tremors and seizures.
• Excess salt / salt dough / homemade play dough — Hypernatremia and neurologic injury can occur after substantial ingestion.
• Avocado — Species dependent: persin is particularly hazardous to birds, rabbits, horses and some other species; large pits can also obstruct the gastrointestinal tract.
• Fruit pits and seeds from Prunus species — Chewed pits/seeds and wilted leaves/stems can release cyanide; the ripe fruit flesh is generally not the toxic portion.
• Hops — Dogs can develop potentially life-threatening hyperthermia after ingestion.
• Green/raw potatoes and potato sprouts — Solanine-type glycoalkaloids.
• Mold-contaminated nuts/grains/pet food — Aflatoxins can cause severe liver injury; visible mold is not required.

Human and Veterinary Medications

Medication exposures are among the most common reasons animal poison-control centers are contacted. Any medication can be hazardous if the dose is high enough or if it is given to the wrong species.

• Acetaminophen (Tylenol and generics) — EXTREME CAT RISK; can also poison dogs. Never give without veterinary direction.
• Ibuprofen, naproxen and other human NSAIDs — Gastrointestinal ulceration and kidney injury; naproxen has a particularly long half-life in dogs.
• Aspirin — Can cause gastrointestinal, renal and acid-base toxicity; cats eliminate salicylates slowly.
• Prescription and OTC pain medications — Including combinations containing acetaminophen, NSAIDs, opioids or other active ingredients.
• Antidepressants — SSRIs, SNRIs, tricyclics, MAOIs and others may cause neurologic and cardiovascular toxicity.
• ADHD/stimulant medications — Amphetamine and methylphenidate products can cause severe agitation, tachycardia, hypertension and hyperthermia.
• Decongestants — Pseudoephedrine and phenylephrine can cause serious cardiovascular and neurologic signs.
• Asthma inhalers — Beta-agonist inhalers can cause severe tachycardia and low potassium when punctured or chewed.
• Sleep aids and sedatives — Benzodiazepines, zolpidem and other agents may cause sedation or paradoxical excitation.
• Cardiac and blood-pressure medications — Beta blockers, calcium-channel blockers, ACE inhibitors and others can be dangerous in small doses.
• Diabetes medications — Insulin and oral hypoglycemics can produce life-threatening hypoglycemia.
• Thyroid medications — Risk varies by drug and species; large ingestions require assessment.
• Vitamin D and vitamin D analogs — Cholecalciferol supplements and prescription calcitriol can cause hypercalcemia and kidney injury.
• Iron-containing vitamins and supplements — Corrosive gastrointestinal injury, shock and liver damage possible.
• Topical medications — 5-fluorouracil cream is EXTREMELY TOXIC to dogs and cats; also beware topical NSAIDs and other human creams.
• Veterinary medications belonging to another animal — Dose and species matter; never assume a medication safe for one pet is safe for another.

Household, Garage, Yard and Recreational Hazards

• Antifreeze / engine coolant (ethylene glycol) — EXTREME EMERGENCY: rapid treatment is critical; causes severe metabolic acidosis and kidney failure.
• Windshield-washer fluid / methanol-containing products — Can cause severe metabolic and neurologic toxicity.
• Rodenticides: anticoagulants — Cause delayed internal bleeding; products vary widely.
• Rodenticides: bromethalin — Causes brain/spinal-cord swelling; there is no specific antidote.
• Rodenticides: cholecalciferol (vitamin D3) — Causes dangerous hypercalcemia and kidney injury.
• Rodenticides: zinc/aluminum phosphide — Releases toxic phosphine gas in the stomach; vomitus can pose a hazard to people and veterinary staff.
• Slug/snail bait containing metaldehyde — Severe tremors, seizures and hyperthermia.
• Insecticides: organophosphates and carbamates — Cholinergic poisoning; formulations vary.
• Permethrin and concentrated pyrethroids — EXTREME CAT RISK, especially dog-only spot-on products; tremors and seizures can occur.
• Amitraz — Found in some veterinary/agricultural products; can cause sedation, bradycardia and glucose abnormalities.
• Flea/tick products used on the wrong species or dose — Never apply a dog product to a cat unless the label specifically permits it.
• Fertilizers — Risk depends on ingredients; products containing iron, insecticide, herbicide or systemic pesticides are more concerning.
• Herbicides — Toxicity varies by active ingredient and formulation; concentrated products may be hazardous.
• Pool and spa chemicals — Concentrated chlorine, bromine, acids and alkalis can cause corrosive injury.
• Household cleaners — Bleach, ammonia, oven/drain cleaners, toilet products and concentrated detergents can cause irritation or corrosive injury.
• Disinfectants — Phenols, quaternary ammonium compounds and concentrated essential-oil cleaners can be hazardous, especially to cats and birds.
• Laundry/dishwasher detergent pods — Concentrated surfactants may cause vomiting, aspiration and ocular injury.
• Batteries — Alkaline/acid contents can cause corrosive burns; button batteries also pose electrical and obstruction hazards.
• Mothballs — Naphthalene and paradichlorobenzene can cause gastrointestinal, neurologic and blood-cell toxicity.
• Hydrocarbons / petroleum distillates — Gasoline, kerosene, lighter fluid, lamp oil, paint thinner and some solvents pose aspiration and systemic risks.
• Paints and solvents — Risk depends on formulation; solvents and heavy metals are more hazardous than most modern water-based paints.
• Lead — Old paint, weights, batteries, fishing tackle, toys and other sources; gastrointestinal and neurologic toxicity.
• Zinc — Pennies minted after 1982, hardware, creams and metallic objects can cause hemolysis and organ injury.
• Iron — Some fertilizers, oxygen absorbers, hand warmers and supplements contain iron.
• Silica gel packets — Usually low toxicity, but the packet can be a choking/obstruction risk; oxygen absorbers may contain iron and are different.
• Glow sticks / glow jewelry — Usually intensely bitter/irritating rather than systemically poisonous; drooling is common.
• Superglue / cyanoacrylate — Usually bonds tissue rather than causing systemic poisoning; expanding polyurethane/Gorilla-type glues can form a gastric foreign body.
• Polyurethane expanding glue — Can expand and harden in the stomach, producing a potentially obstructive foreign body.
• Essential oils and concentrated fragrances — Risk varies with oil, dose, route and species; cats and birds may be especially susceptible.
• Cannabis / THC products — Neurologic depression, ataxia and urinary incontinence may occur; edible products may contain additional toxins such as chocolate or xylitol.
• Nicotine / cigarettes / cigars / chewing tobacco / e-cigarette liquid / nicotine pouches — HIGH RISK: concentrated nicotine can cause rapid neurologic and cardiovascular toxicity.
• Cocaine, amphetamines and other illicit/recreational drugs — Potentially life-threatening neurologic and cardiovascular toxicity.

Toxic Plants — Alphabetical Reference

This table focuses on plants reported to cause systemic toxicity or important gastrointestinal/oral injury in companion animals. It also corrects a common problem with older poison lists: not every member of a broad group such as “cactus,” “fern,” “lily,” “mint,” or “mushroom” has the same toxicity. Scientific identification matters.

Plant-Identification Cautions

• “Lily” is not one toxicologic category. True lilies and daylilies are an extreme kidney-failure emergency in cats, while peace lily and calla lily contain irritating calcium oxalate crystals and do not cause the same syndrome.
• Common names are unreliable. “Laurel,” “ivy,” “fern,” “palm,” “cactus,” “mint” and similar names may refer to botanically unrelated plants.
• The toxic part may differ. Bulbs, seeds, pits, sap, wilted leaves, roots or berries can contain much higher toxin concentrations than other portions.
• Ripe edible fruit may differ from the plant. For example, ripe tomato fruit and ripe peach/cherry/apple flesh are not equivalent to the leaves, stems, pits or seeds.
• Dose and species matter. A plant that causes only mild gastrointestinal irritation in one species can be life-threatening in another.