This list covers 20 poisons, ranging from “False Hellebore” to “Funnel-Web Spider Venom.” These substances come from plants, fungi, venomous animals, and everyday chemicals, and they turn up in gardens, kitchens, medicine cabinets, and industrial settings alike.
Poisons are substances that harm, sicken, or kill a living thing when they enter the body in a high enough amount. Some come from nature, like the foxglove plant that also gave us the heart medicine digoxin, while others are man-made, like the once-popular arsenic tonic Fowler’s Solution. A few, like fugu, are famous precisely because eating them safely takes real skill.
Below you’ll find the table with poison, source, effects, antidote, and description.
Poison: the common name of the substance, so you can quickly identify which plant, animal, or chemical is being discussed.
Source: where the poison comes from, whether that’s a plant, an animal’s bite or sting, or a manufactured product.
Effects: the symptoms you might see after exposure, from mild nausea to serious, life-threatening reactions.
Antidote: the treatment doctors use to counter the poison, or a note that only supportive care is available.
Description: a short explanation of what makes the poison notable, including how it works or why it’s risky.
Poisons
| Poison | Source | Effects | Antidote |
|---|---|---|---|
| False Hellebore | Veratrum plant (roots and leaves) | Severe vomiting, low blood pressure, dangerously slow heartbeat | Atropine and supportive care |
| False Morel | Gyromitra mushroom, containing gyromitrin | Nausea, vomiting, liver damage, seizures | Pyridoxine (vitamin B6) |
| Fentanyl | Synthetic opioid, often found in illicit drugs | Slowed or stopped breathing, unconsciousness, death | Naloxone |
| Fer-de-lance Venom | Bite of the fer-de-lance pit viper | Severe swelling, tissue death, uncontrolled bleeding | Pit viper antivenom |
| Ferrous Sulfate (Iron) | Iron supplement tablets | Vomiting, stomach bleeding, organ failure in overdose | Deferoxamine |
| Fire Ant Venom | Sting of the fire ant | Burning pain, blistering, allergic reactions | Epinephrine for severe allergic reactions |
| Fire Salamander Toxin | Skin secretions of the fire salamander | Muscle spasms, high blood pressure, breathing trouble | No specific antidote; supportive care |
| Firefly Toxin (Lucibufagin) | Body fluids of fireflies | Cardiac poisoning in animals that eat them | No specific antidote |
| Fluoroacetate (Compound 1080) | Synthetic rodenticide, also occurs naturally in some plants | Seizures, irregular heartbeat, heart failure | No specific antidote; supportive care |
| Fluoride (Excess) | Concentrated fluoride supplements or industrial exposure | Nausea, muscle weakness, seizures, cardiac arrest | Calcium gluconate |
| Fly Agaric | Amanita muscaria mushroom | Hallucinations, vomiting, confusion, drowsiness | Atropine for severe cases; mostly supportive care |
| Fool’s Parsley | Aethusa cynapium plant, resembling parsley | Vomiting, drooling, convulsions | No specific antidote; supportive care |
| Formaldehyde | Embalming fluid, industrial chemical, some household products | Irritation of eyes and lungs, tissue damage, cancer risk | No specific antidote; supportive care |
| Formic Acid | Secreted by ants, used in industry | Skin and eye burns, breathing difficulty | No specific antidote; supportive care |
| Fowler’s Solution | Historical arsenic-based tonic (potassium arsenite) | Chronic arsenic poisoning, skin changes, organ damage | Dimercaprol (BAL) |
| Foxglove | Digitalis purpurea plant | Irregular heartbeat, nausea, visual disturbances | Digoxin immune Fab (Digibind) |
| Freon | Refrigerant gas used in air conditioners | Dizziness, irregular heartbeat, suffocation | Oxygen and supportive care |
| Fugu (Tetrodotoxin) | Pufferfish organs, especially liver and ovaries | Numbness, paralysis, respiratory failure | No antidote; requires ventilator support |
| Fumonisin | Fusarium mold growing on corn and grain | Liver and kidney damage, potential cancer risk | No specific antidote |
| Funnel-Web Spider Venom | Bite of the Australian funnel-web spider | Muscle spasms, sweating, respiratory failure | Funnel-web spider antivenom |
Descriptions
False Hellebore
A toxic plant often mistaken for edible wild greens; eating any part can cause dangerous drops in blood pressure and heart rate within hours.
False Morel
A wild mushroom that resembles a true morel but contains a rocket-fuel-like toxin; improperly prepared caps can cause serious liver damage.
Fentanyl
An extremely potent synthetic opioid; even a few grains can suppress breathing enough to be fatal, making it a leading cause of overdose deaths.
Fer-de-lance Venom
One of Central and South America’s most dangerous snakes, its venom destroys tissue and blood-clotting ability, causing painful swelling and internal bleeding.
Ferrous Sulfate (Iron)
A common iron supplement that’s surprisingly dangerous in overdose, especially for children; excess iron damages the gut lining and can shut down organs.
Fire Ant Venom
Fire ants deliver a venom that causes an intense burning sensation and pustules; in allergic people, stings can trigger dangerous whole-body reactions.
Fire Salamander Toxin
This brightly patterned amphibian oozes a toxin called samandarin from skin glands, which can cause muscle convulsions if it enters the body.
Firefly Toxin (Lucibufagin)
Fireflies produce bitter, heart-affecting chemicals that make them distasteful and dangerous to predators like lizards and birds, though harmless to humans.
Fluoroacetate (Compound 1080)
A highly toxic pesticide once widely used to kill rodents and predators, it disrupts the body’s ability to produce energy at the cellular level.
Fluoride (Excess)
While trace fluoride helps prevent tooth decay, swallowing a large concentrated dose can be toxic, disrupting calcium levels and heart function.
Fly Agaric
The iconic red-and-white spotted mushroom of storybooks, it contains compounds that cause hallucinations and stomach upset if eaten raw.
Fool’s Parsley
A weed that closely resembles parsley or chervil, making accidental poisoning a real risk for foragers; it can upset the stomach and nervous system.
Formaldehyde
A pungent preservative used in embalming and manufacturing; inhaling or ingesting it burns tissue, and long-term exposure is linked to cancer.
Formic Acid
The stinging chemical that gives ants their bite, this corrosive acid is also used industrially and can cause serious burns in concentrated form.
Fowler’s Solution
A once-popular Victorian-era “tonic” that was actually a diluted arsenic solution; long-term use caused slow arsenic poisoning and skin discoloration.
Foxglove
A tall, bell-flowered garden plant that’s the natural source of digitalis heart medication; eating its leaves can send the heart into a dangerous rhythm.
Freon
A once-common refrigerant gas that displaces oxygen when inhaled and can trigger fatal heart rhythm problems, a risk linked to inhalant abuse.
Fugu (Tetrodotoxin)
The prized but risky Japanese delicacy made from pufferfish, whose organs contain a toxin so potent that improperly prepared fugu can be fatal.
Fumonisin
A toxin produced by mold that contaminates stored corn, posing a long-term health risk to people and livestock that eat affected grain.
Funnel-Web Spider Venom
One of the world’s most venomous spiders, its bite can cause rapid, severe symptoms, though antivenom has made deaths extremely rare today.