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Poisoning is when a person is exposed to a substance that can damage their health or put their life in danger.

Poisoning is a common health problem, resulting in around 120,000 hospital admissions each year in England for example. Most cases of poisoning happen at home and children under five have the highest risk of accidental poisoning.
The most common way a person becomes poisoned is by swallowing a harmful substance, although you can also be poisoned by:

  • inhaling a harmful substance such as carbon monoxide
  • injecting a harmful substance such as heroin
  • harmful substances, such as pesticides, splashing on your skin or eyes
  • being poisoned by an insect or animal bite, such as a snake, though this is rare in the UK
  • overdosing on an illegal drug or medication

The symptoms of poisoning will depend on the type of poison and the amount taken in, but general things to look out for include:

  • being sick
  • stomach pains
  • high temperature
  • drowsiness and fainting fits

If a child has a sudden, unexplained illness, they may have been poisoned, especially if they are drowsy and confused. 

What to do

If you suspect that someone has taken an overdose or has been poisoned do not try to treat them yourself. Get medical help immediately.

If they do not appear to be seriously ill then call NHS Direct Wales on 0845 46 47 for advice.

If they are showing signs of being seriously ill, such as vomiting, loss of consciousness, drowsiness or seizures (fits) call 999 for an ambulance, or take the person to your local A&E department.

Read more about what to do if you think someone has been poisoned.

Types of poisons

One of the most common ways a person is poisoned is by taking an overdose of medication.

This can include both over-the-counter medications such as paracetamol and prescription medications such as antidepressants.

Other potential poisons include:

  • household products such as bleach
  • cosmetic items such as nail polish
  • some types of plants and fungi
  • certain types of chemicals and pesticides

In around one in four reported cases of poisoning the person intentionally poisoned themselves as either an act of self-harm or an attempt at suicide.

Read more about the causes of poisoning.


A person who is poisoned is normally admitted to hospital for observation. A substance known as active charcoal may be given to stop the poison being absorbed into the blood.

There are also several medications known as antidotes that can act against the harmful effect of a specific poison. For example, the antidote to paracetamol poisoning is called N-acetylcysteine, which protects the liver against the harmful effects of paracetamol.

Of those people who are admitted to hospital for poisoning, fewer than 1 in 100 dies.

Read more about treating poisoning.


There are several steps you can take to reduce your (or your child’s) risk of poisoning. These include carefully reading the patient information leaflet that comes with your medication and making sure any poisonous substances are locked away out of the sight and reach of your children.

Read more about preventing poisoning.

Alcohol poisoning

Drinking too much alcohol in a short space of time can lead to poisoning.

Read more about alcohol poisoning.

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The symptoms of poisoning depend on the substance and the amount that you take in.

Some poisonous substances, such as carbon monoxide, interfere with the blood's ability to carry oxygen. Others, such as bleach, burn and irritate the digestive system.

Parents and carers should be aware of sudden, unexplained illness in young children, particularly if they are drowsy or unconscious, as poisoning could be the cause.

If you suspect that someone has swallowed a poisonous substance, seek immediate medical advice. Read more about what to do if you think someone has been poisoned.

General symptoms

General symptoms of poisoning can include:

  • feeling sick
  • being sick
  • diarrhoea
  • stomach pain
  • drowsiness, dizziness or weakness
  • high temperature of 38°C (100.4°F) or above
  • chills (shivering)
  • loss of appetite
  • headache
  • irritability
  • difficulty swallowing (dysphagia)
  • producing more saliva than normal
  • skin rash
  • burns around the nose or mouth
  • double or blurred vision
  • seizures (fits)
  • coma (in severe cases)

Symptoms of medication overdose

If you take a medication overdose, you may experience any of the specific symptoms below, as well as the more general symptoms above.

The most common medications involved in cases of poisoning are listed below.


Paracetamol is a widely used over-the-counter painkiller.

Specific symptoms of paracetamol poisoning include:

  • jaundice (yellowing of the skin and the whites of the eyes)


Aspirin was used as a painkiller in the past but is now increasingly used for its blood-thinning properties to prevent blood clots.

Specific symptoms of aspirin poisoning include:

  • rapid breathing
  • tinnitus (ringing in the ears)

Tricyclic antidepressants

Tricyclic antidepressants are used to treat depression as well as a number of other mental health conditions such as panic disorder and obsessive compulsive disorder (OCD). Some types of tricyclic antidepressants can also be used to treat nerve pain.

Specific symptoms of poisoning with tricyclic antidepressants include:

  • excitability
  • dry mouth
  • large pupils
  • irregular heartbeat
  • low blood pressure
  • a rapid heart rhythm

Selective serotonin reuptake inhibitors (SSRIs)

SSRIs are a newer type of antidepressant that are also used to treat a number of other mental health conditions such as OCD and anxiety disorder.

Specific symptoms of SSRI poisoning include:

  • feeling agitated
  • tremor (shaking)
  • uncontrolled movement of the eyes (nystagmus)

In severe cases it can also cause:


Beta-blockers are used to treat a number of conditions that affect the heart or blood such as high blood pressure, angina and heart failure.

Specific symptoms of poisoning with beta-blockers include:

  • low blood pressure
  • a low pulse rate (below 60 beats a minute)

Calcium-channel blockers

Calcium-channel blockers are used in the treatment of high blood pressure and angina.

Specific symptoms of calcium-channel blocker poisoning include:

  • chest pain
  • low blood pressure
  • a low pulse rate (below 60 beats a minute)
  • blue skin
  • breathing problems


Benzodiazepines are a type of tranquiliser that are often used on a short-term basis to treat anxiety and sleeping problems (insomnia).

Specific symptoms of poisoning with benzodiazepines include:

  • co-ordination and speech difficulties
  • low blood pressure
  • hypothermia (where body temperature drops below 35°C/95°F)
  • shallow breathing


Opioids are a type of stronger painkillers that are used to treat moderate to severe pain. Opioids include codeine and morphine as well as the illegal drug heroin.

Specific symptoms of opioid poisoning include:

  • small pupils
  • shallow breathing
  • blue skin
  • fluid on the lungs

Stimulant overdose

If you take too much of a stimulant-like drug such as cocaine, amphetamine, crack or ecstasy, overdose symptoms can include:

  • anxiety and paranoia (feeling that people are out to get you)
  • chest pain
  • high temperature
  • high blood pressure
  • rapid breathing and heartbeat
  • mental confusion
  • hallucinations (seeing or hearing things that are not real)
  • stomach cramps

Cannabis overdose

If you smoke (or eat) too much cannabis then you may experience the following symptoms:

  • paranoia
  • hallucinations
  • numbness in your arms and legs
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Medications can be the most common cause of poisoning and are responsible for more than half of all cases.

The medications most commonly linked to poisoning are:

  • paracetamol
  • aspirin
  • tricyclic antidepressants
  • selective serotonin reuptake inhibitors (SSRIs)
  • beta-blockers
  • calcium-channel blockers
  • benzodiazepines
  • opioids

However, all medications have the potential to be harmful if taken at too high a dose or taken by someone who has not been prescribed them, such as a child.

Household products

The second most common cause of poisoning is household products, which account for around one in five cases.

These can include:

  • cleaning products, such as bleach, caustic soda and disinfectant
  • cosmetics, such as baby oil, shampoo and nail varnish remover
  • DIY products, such as paint, glue and wallpaper paste
  • garden products, such as weedkiller and rat poison

Insects and snakes

Bees and wasps inject poison into your skin when they sting you, which can cause pain, swelling and itchiness.

Bites from poisonous snakes can cause diarrhoea and sickness. The adder is the only poisonous snake that lives in the UK.

How severely you are affected by a poisonous bite or sting depends on the amount of venom (poison) injected and whether you are allergic to it.

Read more about insect stings and snake bites.


Food can sometimes cause poisoning if:

  • it goes mouldy
  • it becomes contaminated with bacteria from raw meat
  • it has not been prepared or cooked properly

Read more about food poisoning.

Carbon monoxide

Carbon monoxide is a poisonous, odourless gas that is produced by the incomplete burning of fuels, such as gas, wood or petrol. These types of fuels are used in many household appliances, such as heaters and cookers.

If appliances are not regularly serviced and well maintained, carbon monoxide can leak from them without you realising, which can cause loss of consciousness and death.

Read more about carbon monoxide poisoning.

Younger children

Younger children under the age of six who are able to walk have an increased risk of poisoning. This is because they often put things in their mouth without realising they are harmful.

Also, as their bodies are smaller they are more vulnerable to the harmful effects of certain substances.

The most common substances involved in cases of child poisoning are:

  • cosmetics
  • cleaning products
  • painkillers
  • medications that come in cream, lotion or ointment form
  • foreign bodies, such as small coins or batteries
  • cough and cold medications
  • plants
  • vitamins
  • antibiotics
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What to do

Being poisoned can be life threatening. If someone has swallowed a poisonous substance, do not try to treat them yourself. Get medical help immediately.

If they are showing signs of being seriously ill then call 999 for an ambulance, or take them to your local A&E department.

Symptoms associated with serious poisoning include:

  • being sick
  • abdominal pain
  • drowsiness or reduced levels of consciousness
  • breathing difficulties
  • seizures (fits)

But if a person does not appear to be seriously ill then telephone NHS Direct Wales on 0845 46 47 for advice.

How to help

If you think someone has swallowed poison and they appear to be unconscious, try to wake them and encourage them to spit out any pills. Do not put your hand into their mouth and do not try to make them sick.

If you are waiting for medical help to arrive, lie the person on their side with a cushion behind their back and their upper leg pulled slightly forward, so they do not fall on their face or roll backwards.

Wipe any vomit away from their mouth and keep their head pointing down to allow any vomit to escape without them breathing it in or swallowing it.

Do not give them anything to eat or drink.

Poisonous fumes

If you think someone has inhaled poisonous fumes, assess the situation first and do not put yourself in danger. Call for help and, if it is safe to do so, remove the person from the contaminated area.

Before entering the area, take two or three deep breaths and hold your breath until you come out. As soon as you are out of the affected area, call 999.

Check that the person's airway is open. To do this lift their chin with one hand and gently tilt the head back. Then check that they are still breathing by placing your cheek close to their mouth to feel their breath.

If they are not breathing, begin cardiopulmonary resuscitation (CPR) if you know how to (read more about how to perform CPR). If the person is breathing and conscious, cover them with a blanket and check them every 10 minutes to make sure they are still breathing until the ambulance arrives.

How to help medical staff

Medical staff will need to take a detailed history to effectively treat a person who has been poisoned. When the paramedics arrive or when you arrive at A&E, give them as much information as you can, including:

  • What substances you think the person may have swallowed.
  • When the substance was taken (how long ago).
  • Why the substance was taken – whether it was an accident or deliberate.
  • How it was taken (for example, swallowed).
  • How much was taken (if you know).

Give details of any symptoms that the person has had, such as whether they have been sick.

If they have been sick, collect a sample of their vomit as it may help medical staff to identify the poison.

Medical staff may also want to know:

  • The person's age and estimated weight.
  • Whether they have any existing medical conditions.
  • Whether they are taking any medication (if you know).

If possible, give medical staff the container that the substance came in to give them a clear idea of what it is. If you do not know what caused the poisoning, blood tests may be needed to identify the cause.

Hospital treatment

Some people who have swallowed a poisonous substance or have overdosed on medication will be admitted to hospital for examination.

Possible treatments that can be used to treat poisoning include:

  • Activated charcoal - healthcare professionals sometimes use activated charcoal (charcoal that has been treated so that it is pure carbon) to treat someone who has been poisoned. The charcoal binds to the poison and stops it from being further absorbed into the blood.
  • Antidotes - these are substances that either prevent the poison from working or reverse the effects of the poison.
  • Sedatives - these may be given if the person is agitated.
  • A ventilator (breathing machine) - this may be used if the person stops breathing.
  • Anti-epileptic medicine - this may be used if the person has seizures.

Tests and investigations

Investigations may include blood tests and an electrocardiogram.

A blood test can be used to check the levels of chemicals and glucose in a person’s blood. They may be used to perform a toxicology screen (tests to determine how many drugs or medication a person has taken) and a liver function test (which indicates how damaged the liver is).

Go to the Lab Tests Online website for more information on liver function tests.

An electrocardiogram (ECG) is an electrical recording of the heart to check that it is functioning properly.

More information:

Deliberate poisoning

If you or someone you know poisoned themselves as an act of self-harm or an attempt at suicide then further psychiatric care will be required.

Read more about treating self-harm and getting help if you are feeling suicidal.

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Preventing poisoning in children

The most common form of poisoning is from medication. The following advice should help prevent accidental poisoning by medication:

  • Always read the patient information leaflet that comes with your medication carefully and take your dosage exactly as recommended.
  • If you are unsure about any of the instructions or have further questions, ask your pharmacist or GP for advice.
  • Some medications should not be taken with alcohol or certain types of food. Check if this is the case for your medication.
  • Some medications can react unpredictably if taken with other medications, including herbal remedies. Always check before combining different medications.
  • Never take a medication that has been prescribed for somebody else.
  • Keep all medication out of reach of children.


The points provided below should help prevent accidental poisoning in your children.

  • Make sure all medicines, cleaning products, chemicals and potentially harmful cosmetics, such as nail varnish, are locked away out of the sight and reach of children.
  • Do not store medicines, cleaning products or chemicals near food.
  • Keep all chemicals in their original containers and never put medicines or chemicals, such as weedkiller, in soft-drinks bottles.
  • When encouraging children to take medicine (when they are sick), do not refer to tablets as sweets.
  • Do not leave old medicines lying around. Take them to your local pharmacist to dispose of safely.
  • Keep cigarettes and tobacco out of the reach of children and do not smoke in front of children.
  • Small batteries, such as those used for television remote controls, can be easily swallowed, so keep them out of the reach of children.
  • Whenever possible, buy medicines that come in child-proof containers.
  • Rinse out medicine or cosmetic containers and dispose of them in a place where children cannot reach them.
  • Do not take or give medicines in the dark to avoid taking an incorrect dosage.

If you have young children, be extra careful when you have guests to stay or when you go to visit other people. If your friends and relatives do not have children, they may not think to keep certain items out of the reach of children and their home is unlikely to be childproof.

Keep an eye on your children at all times and politely ask guests to keep items such as alcohol and cigarettes out of their reach.

Read more about preventing accidents to children in the home.

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