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5 Medicines Derived From Poisons

These ‘natural’ substances can kill you — or save your life.

By Allison Futterman
Mar 16, 2022 4:30 PM


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Poisons as medicine: It’s not a phrase that sparks a lot of comfort. However, people have been using toxins for health purposes throughout history. Plants and animals provide rich sources of chemicals that can be both deadly and medicinal. Because they are fixed in the ground, plants have become skilled at producing chemical defenses against organisms that eat them and plants that may invade their space. Some animals have developed similar defenses. Poison dart frogs, for example, can secrete a toxin through their skin, making them a dangerous and unappetizing snack for predators. Though certain plants and organisms produce toxins, scientists have found ways to use those toxins in medicine to help improve lives. Here are five medicines derived from poisonous plants and natural materials.



Botox has a variety of medicinal uses. As a toxin produced by the bacterium Clostridium botulinum, this bacterium can cause botulism, a type of life-threatening food poisoning. Found on plants, in soil, water and the intestinal tracts of animals, Botox, the trademark named for botulinum toxin, can be an effective treatment for health issues when used in small doses. These include chronic migraine, blepharospasm (eyelid spasms), severe sweating, overactive bladder and cervical dystonia. It’s commonly used to treat wrinkles. Botox works by blocking the signal between nerves and muscles, preventing or lessening muscle contraction. Although generally well tolerated, Botox can cause side effects like pain and swelling at the injection site as well as flu-like symptoms. Typically, this is more common with therapeutic use than cosmetic procedures, perhaps due to higher doses and/or underlying disease.


(Credit:Mariola Anna S/Shutterstock)

The heart medication digoxin (digitalis) is made from the dried leaves of the foxglove plant. British physician William Withering first wrote about — and popularized — medicinal uses for foxglove in 1785. Classified as a cardiac glycoside, digoxin works by affecting calcium activity. This results in less strain on the heart, and maintenance of a normal, steady heartbeat. Foxglove poisoning can occur when people suck on the plant’s flowers or eat the leaves, stems, seeds — or take too much medication derived from foxglove. Signs of foxglove poisoning include slow/irregular heartbeat, low blood pressure, blurry vision, confusion and loss of appetite. From 1987 to 2003, nurse Charles Cullen murdered at least 29 of his patients, often using digoxin



This foul-smelling, pale yellow plant with bell-shaped flowers can grow up to three feet tall and has sticky, hairy leaves. There have been 34 alkaloids discovered in henbane, including scopolamine, hyoscyamine and atropine. These drugs are anticholinergics, which work by inhibiting  the central and parasympathetic nervous systems by interfering with neuron receptors. Side effects include seizures, hallucinations, confusion, flushing, decreased sweating and impaired vision. Alkaloid drugs offer a wide variety of medical uses, due to their anticholinergic and antispasmodic properties. These include:

  • Relieving bladder, intestinal and stomach spasms, and cramps. 

  • Preventing nausea and vomiting.

  • Aiding in relaxation, maintaining normal heartbeat and decreasing saliva production during surgery.

  • Treating certain types of poisoning.

Opium Poppy Plant


Papaver somniferum is the scientific name for the opium poppy plant. This flowering plant blooms annually and reaches heights between 3 and 16 feet tall. Known for pain-blocking abilities, the seeds contain opiates in the form of natural alkaloids. Common medication names are morphine and codeine. Oxycodone and hydrocodone are semi-synthetic derivatives. These medications are highly addictive and have led to the opioid epidemic in the U. S. They should only be taken when and as prescribed or they can lead to extreme addiction and death by overdose. People can test positive on drug tests after eating poppy seeds on bagels or in baked goods.


(Credit:Sonis Photography/Shutterstock)

Rodenticides are poisons used for killing rats and mice. One such product is warfarin, a chemical found in plants like sweet clover. It kills rodents by preventing their ability to clot blood, which causes internal bleeding. Warfarin was used as a rodenticide dating back to 1948 — and was approved as a blood thinner for humans in 1954. While considered an efficacious anticoagulant, warfarin has a narrow therapeutic ratio — meaning that small differences in dosing can lead to adverse reactions. Certain foods —  especially leafy greens like spinach, as well as Brussels sprouts and broccoli —  can lessen warfarin’s effectiveness. Patients taking this medication must undergo frequent blood tests to monitor their internalized normal ratio (INR) levels, a measurement of how long blood takes to clot. If INR is too high, there’s an increased risk of bleeding. Too low and people risk a blood clot.

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