Poisoning Facts

Picture of a man with abdominal pain.
Picture of a man with abdominal pain.

If you or someone you know has swallowed or breathed in a poison, and you or they have serious signs or symptoms (nausea, vomiting, pain, trouble breathing, seizure, confusion, or abnormal skin color), you must either call an ambulance for transport to a hospital emergency department or call a poison control center for guidance. The National Poison Control Center phone number in the U.S. is 1-800-222-1222.

If the person has no symptoms but has taken a potentially dangerous poison, you should also call a poison control center or go to the nearest emergency department for an evaluation.

Poison is anything that kills or injures through its chemical actions. Most poisons are swallowed (ingested). The word poison comes from the Latin word - potare - meaning to drink. But poisons can also enter the body in other ways:

  • By breathing
  • Through the skin
  • By IV injection
  • From exposure to radiation
  • Venom from a snake bite or insect bite

What Are Types of Poisoning?

Poisons include highly toxic chemicals not meant for human ingestion or contact, such as cyanide, paint thinners, or household cleaning products.

Many poisons, however, are substances meant for humans to eat, including foods and medicines.


  • Some mushrooms are poisonous
  • Drinking water contaminated by agricultural or industrial chemicals
  • Food that has not been properly prepared or handled


Drugs that are helpful in therapeutic doses may be deadly when taken in excess.

Examples include:

What Are the Symptoms of Poisoning?

Signs and symptoms of poisoning are so wide and variable that there is no easy way to classify them.

  • Some poisons enlarge the pupils, while others shrink them.
  • Some result in excessive drooling, while others dry the mouth and skin.
  • Some speed the heart, while others slow the heart.
  • Some increase the breathing rate, while others slow it.
  • Some cause pain, while others are painless.
  • Some cause hyperactivity, while others cause drowsiness. Confusion is often seen with these symptoms.

When the cause of the poisoning is unknown

A big part of figuring out what type of poisoning has occurred is connecting the signs and symptoms to each other, and to additional available information.

  • Two different poisons, for example, may make the heart beat quickly. However, only one of them may cause the skin and mouth to be very dry. This simple distinction may help narrow the possibilities.
  • If more than one person has the same signs and symptoms, and they have a common exposure source, such as contaminated food, water, or workplace environment, then poisoning would be suspected.
  • When two or more poisons act together, they may cause signs and symptoms not typical of any single poison.


Certain poisons cause what toxicologists call toxidromes - a contraction of the words toxic and syndrome. Toxidromes consist of groups of signs and symptoms found together with a given type of poisoning.

  • For example: Jimson weed, a plant smoked or ingested for its hallucinogenic properties, produces the anticholinergic toxidrome: Rapid heart rate, large pupils, dry hot skin, retention of urine, mental confusion, hallucinations, and coma.
  • Most poisons either have no associated toxidrome or have only some of the expected features of the toxidrome.

Delayed Onset of Poisoning Symptoms

A person can be poisoned and not show symptoms for hours, days, or months. Cases of poisoning with a prolonged onset of symptoms are particularly dangerous because there may be a dangerous delay in obtaining medical attention.

  • Acetaminophen (Tylenol) is considered a safe drug, but is toxic to the liver when taken in large quantities. Because it acts so slowly, 7 to 12 hours may pass before the first symptoms begin (no appetite when normally hungry, nausea, and vomiting).
  • The classic example of a very slow poison is lead. Before 1970, most paints contained lead. Young children would eat paint chips and, after several months, develop abnormalities of the nervous system.

When the illness may be poisoning - or may not be poisoning

Some signs and symptoms of poisoning can imitate signs and symptoms of common illnesses.

  • For example, nausea and vomiting are a sign (vomiting) and symptom (nausea) of poisoning. However, nausea and vomiting can also be found in many illnesses that have nothing to do with poisoning. Examples include:
  • Almost every possible sign or symptom of a poisoning can also be caused by a non-poison-related medical problem.

What Should You Do if You Suspect Poisoning?

Call the U.S. National Poison Control Center at 1-800-222-1222 if you have questions about possible poisoning. You can also go directly to your hospital's emergency department.

  • Don't assume over-the-counter medications are safe even if taken in excess. Call the poison control center for advice.
  • With many pills, it may take several hours or longer for symptoms to develop. Do not wait for symptoms to develop, call the poison control center for advice.

Go to your hospital's emergency department if any of the following occurs:

  • If someone looks ill after a poisoning or possible poisoning.
  • An infant or toddler who may have ingested a poison, even if the child looks and feels fine.
  • Anyone who has taken something in an attempt to harm himself or herself, even if the substance used is not known to be harmful.
  • When take the person to the hospital's emergency department, take all the medicine bottles, containers (household cleaners, paint cans, vitamin bottles), or samples of the substance (such as a plant leaf).

How Is Poisoning Diagnosed?

A combination of history, physical examination, and laboratory studies will help reveal the cause of most poisonings. Frequently, treatment must begin before all information is available.

History: As a family member or friend of a poisoned person, you can greatly assist the doctor and provide valuable clues by telling the doctor about these details:

  • Everything the person ate or drank recently
  • Names of all prescription and over-the-counter medications the person is taking
  • Exposure to chemicals at home or at work
  • Whether others in the family or at work have been similarly ill or exposed
  • Whether the person has any psychiatric history to suggest an intentional ingestion (suicide attempt)

Testing: Many poisons can be detected in the blood or urine. However, a physician cannot order "every test in the book" when the diagnosis is unclear. The tests ordered will be based on information revealed in the history and physical exam.

What Is the Treatment for Poisoning?

Poisoning can occur from a variety of factors like medications, illicit drugs, foods, and attempts to harm ones life. Poisoning is a medical emergency and cannot be treated at home. If think you or someone you know shows the symptoms of poisoning as described previously, seek medical care immediately.

Poisoning Self-Care at Home

If you or someone you know has swallowed or breathed a poison and you or they have signs or symptoms, such as nausea, vomiting, pain, trouble breathing, seizure, confusion, or abnormal skin color, you must call either an ambulance or the U.S. National Poison Control Center at 1-800-222-1222 for guidance. This number is routed to the poison control center that serves your area.

  • Post the telephone number (along with police, fire, and 911 or equivalent) near your home phones.
  • Do not induce vomiting or give syrup of Ipecac.
    • Ipecac was previously used to induce vomiting in poisoned patients where there was a chance to get the toxin out of the body. Several advisory bodies such as the American Association of Poison Control Centers and the American Academy of Pediatrics have recommended that Ipecac NOT be used and that it should not even be kept in the household. For more information on this subject go to: http://www.poison.org/prepared/ipecac.asp
  • Do not give activated charcoal at home. Allow medical personnel to decide if this treatment is appropriate.
  • The poison control center will instruct you what to do or if an antidote is readily available.

What Is the Medical Treatment Poisoning?

Elimination: Get rid of the unabsorbed poison before it can do any harm.

  • If the person is unconscious, the doctor will put a flexible, soft, plastic tube into the windpipe to protect the person from suffocating in his or her own vomit and to provide artificial breathing (intubation).
  • Once the poison has moved past the stomach, other methods are needed.
  • Activated charcoal acts as a "super" absorber of many poisons. Once the poison is stuck to the charcoal in the intestine, the poison cannot get absorbed into the bloodstream. Activated charcoal has no taste, but the gritty texture sometimes causes the person to vomit. To be effective, activated charcoal needs to be given as soon as possible after the poisoning. It does not work with alcohol, caustics, lithium (Lithobid), or petroleum products.
  • Whole bowel irrigation requires drinking a large quantity of a fluid called Golytely. This flushes the entire gastrointestinal tract before the poison gets absorbed.

Antidotes: Some poisons have specific antidotes. Antidotes either prevent the poison from working or reverse the effects of the poison.

  • Atropine is an antidote for certain nerve gases and insecticides. During Operation Desert Storm, all military personnel were issued atropine injectors when it was feared that the enemy would use nerve gas.
  • A common antidote is N-acetylcysteine (Mucomyst), which is used to neutralize acetaminophen (Tylenol) overdoses. Acetaminophen, in normal doses, is one of the safest medications known, but after a massive overdose, the liver is damaged, and hepatitis and liver failure develop. Mucomyst works as an antidote by bolstering the body's natural detoxification abilities when they are overwhelmed.
  • It may also be possible to reverse the harmful effect of a drug even if no antidote exists.
    • If a person with diabetes takes too much insulin, a dangerously low blood sugar (hypoglycemia) will cause weakness, unconsciousness, and eventually death. Sugar given by mouth or IV is an effective treatment until the insulin wears off.
    • When the poison is a heavy metal, such as lead, special medicines (chelators) bind the poison in the bloodstream and cause it to be eliminated in the urine.
    • Another "binder" is sodium polystyrene sulfonate (Kayexalate), which can absorb potassium and other electrolytes from the bloodstream.
    • If a person has been bitten by a poisonous snake, and antivenin may be used to counteract the toxins.

General supportive measures: When there are no specific treatments, the physician will treat signs and symptoms as needed.

  • If the person is agitated or hallucinating, a sedative can be given to calm the person until the drug wears off.
  • A ventilator can be used to breathe for anyone who has stopped breathing from a poisoning.
  • Antiseizure medicines can be used to treat or prevent seizures.

What Is the Prognosis for Poisoning?

The key to a good outcome is rapid recognition that a poisoning has occurred and rapid transport to a qualified medical facility when indicated.

  • When medical care (and use of the U.S. National Poison Control Center-1-800-222-1222) is provided promptly, the vast majority of people survive poisonings.
  • Poor outcomes can occur when these are the cause of the poisoning:
    • Highly toxic substances such as cyanide
    • Substances that injure body tissues immediately (lye or acids, for example)
    • Poisoning as a result of exposure over time, often unrecognized (examples include polluted water, workplace exposures, and lead)

Health Solutions From Our Sponsors

"Poisoning First Aid." RedCross.

"Poisoning." U.S. National Library of Medicine. Updated Sept 21, 2016.