Poisons are substances that can harm the body. Poisons can be swallowed, inhaled, absorbed or injected. Accidental poisoning usually involves children or the elderly.

About poisons
Symptoms of poisoning
Treatment of poisoning
Prevention of poisoning

About poisons

Many common household substances can be poisonous.

  • Medicines may be safe at the recommended dose, but can be poisonous if you take an overdose.
  • Cleaning and washing products such as bleach and dishwasher tablets/powder can be harmful even in small amounts if you don’t use them correctly.
  • Other household chemicals such as plant food, paints, solvents, firelighters, weedkiller or slug pellets are often poisonous.
  • Some toiletries such as hair dyes, chemical treatments and nail varnish remover can be harmful.
  • Gases, such as carbon monoxide, can be poisonous.

Some household products have an orange panel on the back to warn you that they can be harmful if you don’t use them correctly. Other products may have a risk phrase, such as 'harmful if swallowed' or 'irritating to eyes'. You should always follow the instructions given on the product label when using any chemicals or household products.

You can also be poisoned by:

  • bites from animals, including snakes
  • insect bites or stings
  • fish or jellyfish stings
  • germs in your food (food poisoning), such as bacteria and mould that produce toxins (a toxin is a poison produced by a living organism)
  • wild plants, berries, or mushrooms, which can be irritating to your skin or harmful if you swallow them

Children are most at risk from accidental poisoning at home, about four out of 10 cases of accidental poisoning occur in children under 10. Children aged around two are most at risk.

Symptoms of poisoning

Different poisons affect your body in different ways and can take effect quickly or over time. The risk depends on a variety of factors including:

  • the amount swallowed or injected
  • the length of exposure (through ingestion, inhalation or skin contact)
  • the time since exposure
  • the age and weight of the person affected

As such, the range of symptoms can be broad and varied. If someone suddenly becomes ill for no apparent reason, or acts strangely, you should consider poisoning a possibility, particularly if you find him or her near a potentially poisonous substance.

Symptoms of poisoning can include:

  • feeling sick or vomiting, abdominal (tummy) pain, diarrhoea
  • dizziness, weakness or drowsiness
  • fever or chills (shivering)
  • fast or irregular pulse
  • headache, confusion or irritability
  • pain on swallowing or production of more saliva than usual
  • burns around the nose or mouth
  • double or blurred vision
  • seizures (fits)
  • stupor (being sleepy or unresponsive) or unconsciousness

Treatment of poisoning

Being poisoned can be life-threatening. Appropriate first aid can help minimise the harm to the person who is poisoned. For simplicity the person (casualty) is referred to in the male gender throughout.

If you think someone has swallowed, injected or inhaled a poison or has taken an overdose of drugs and appears to be unconscious, try to rouse him. If the person responds, you shouldn't move him; instead try to find out what is wrong and get help if you need it. If he is unresponsive, you should first shout for help and then open the airway by:

  • turning the person on his back
  • tilting his head back
  • lifting his chin

Ask someone to phone for an ambulance. If you're on your own, you should do this yourself. Be ready to give as much of the following information as you can to the paramedics and to the doctor or nurse in the Accident and Emergency department.

  • The name of what was swallowed, injected or inhaled if you know it. If possible, keep the container and make a note of how much has been taken.
  • The estimated time that the poison was taken or used.
  • Whether or not the person has vomited.
  • Whether you think it was accidental or deliberate.
  • Whether the person suffers from any chronic illness (eg heart disease) or takes any medication (if you know).

If the person is unconscious and breathing normally, you should turn him into the recovery position.

If the person is unconscious and isn't breathing normally, you should perform emergency resuscitation (cardiopulmonary resuscitation or CPR), but only if you know how. If you think the poison was swallowed, use the mouth-to-nose method, or preferably, use a pocket mask or face shield for rescue breathing. This way you avoid any contact with traces of poison or vomit that might remain around the person's mouth. Don't stop unless the person begins breathing normally or qualified help arrives to take over.

If the person has pills in his mouth, try to get him to spit them out. You can give them to the hospital staff to help identify the cause of poisoning.

Don't try to make the person sick as vomiting can cause even more damage. If the person has been sick, collect a sample of the vomit to take to hospital. This may help staff identify the poison.

Inhalation of poisonous fumes

If you suspect that someone has inhaled poisonous fumes, first assess the situation and the risk you're in – don't put yourself in danger. Call for help and if necessary call the fire brigade.

Once you have made sure that the area is safe, check the person's airway and breathing. If he isn't breathing normally, call for emergency help or preferably get someone to call for you. Don't expose yourself to the person's breath. If you know how to, begin CPR, but use chest compressions only. You should continue at a rate of 100 to 120 compressions per minute. Don’t stop unless the casualty shows signs of regaining consciousness, such as coughing or opening eyes, and starts to breathe normally.

If the person is breathing and unconscious, put him or her into the recovery position and call for emergency help or preferably get someone to call for you. Check his breathing regularly until help arrives.  

If the person is conscious, make sure his airway is open and that he can breathe comfortably and you can monitor his condition. Call for emergency help or preferably get someone to call for you.

·Carbon monoxide poisoning Carbon monoxide is a colourless, odourless, tasteless gas. It's produced by incomplete burning of fuels, including gas, wood or petrol (eg indoor heating systems, car engines, fires and cooking appliances).

Dangerous levels of carbon monoxide can build up if equipment (eg a boiler) is faulty or poorly maintained, or by burning fuels in an enclosed space.

Carbon monoxide is absorbed through your lungs into your blood. It reduces the blood's ability to carry oxygen around your body. Symptoms of carbon monoxide poisoning can include feeling sick, dizziness, diarrhoea, headache, drowsiness and confusion. It can result in chest pain, changes to your breathing and heart rate, loss of consciousness and eventually death.

If you suspect that you or someone else is affected by carbon monoxide poisoning, leave the area and seek urgent medical attention.

The treatment for carbon monoxide poisoning involves breathing pure oxygen (oxygen therapy) to help replace the carbon monoxide in the blood.

Contamination of the skin or eyes

Chemicals can burn or irritate your skin or eyes. If you spill a harmful chemical on yourself you should:

  • brush off the chemical if it's a powder
  • run the affected area under cold water for 20 minutes
  • remember to wash away from other parts of your body
  • seek urgent medical attention

If you spill a chemical into your eye, then you should flush your eye with water or sterile fluid for at least 10 minutes. You should hold a pad over your eye and seek urgent medical attention.

If you’re treating someone else, wear gloves, apron and face protection, if necessary.

Always read the label and follow the manufacturer's instructions when using chemicals or household products.

Prevention of poisoning

You can reduce the likelihood of accidental poisoning in your home.

  • Store all medicines, vitamins and potentially poisonous substances in their original containers with a clear label. Keep them in an area that is out of sight and reach of children.
  • Check your garden for poisonous plants and remove them. Children should be taught not to eat any part of a growing plant.
  • Have your boiler and gas appliances serviced regularly to reduce the risk of carbon monoxide poisoning, and make sure that bedrooms in particular have adequate ventilation. Consider installing carbon monoxide alarms in your home.
  • Don't block air vents, flues or chimneys and don't have indoor fires or stoves without proper ventilation to the outdoors.

Appropriate first aid can greatly improve a person's chances of a full recovery. You can learn about providing first aid in a wide range of accidents and emergencies by taking a course. Several organisations offer first aid courses, including vital instructions on CPR.


·Which animals in the UK are venomous or poisonous?

·What should I do if I have taken too many paracetamol tablets?

·What can I do to prevent carbon monoxide poisoning in my home?

Which animals in the UK are venomous or poisonous?

There are no highly venomous animals in the UK – the only venomous snake is the adder. Some animal bites and stings can cause pain and inflammation. In some people, they can cause a severe allergic reaction (anaphylaxis) requiring immediate medical help.


A venomous animal, or insect, is one that produces a toxin that is delivered by stinging or biting; for example, snakes and wasps can be venomous. Some poisonous animals produce a toxin that has to be eaten or touched to be harmful.
The adder is the only venomous snake in the UK and bites are rarely lethal. Adders aren't aggressive and they only bite as a form of defence. You can identify an adder by the dark zigzag running down the length of the snake and an inverted 'V' shape on the neck. However, some adders are entirely black and can be mistaken for some other species such as grass snakes, smooth snakes and slow worms.

If you think you have been bitten by an adder, go to hospital immediately. Use a splint or sling to stop you from moving the affected area. Don't try to slow the bleeding from the wound and don't try cutting or sucking the wound. Don't try to catch the snake or bring it to the hospital.

Weaver fish are common on sandy beaches and may sting you if you tread on them. If you're stung by a weaver fish, it will be very painful. You should immerse the affected area in very hot (but not scalding) water and you can take over-the-counter painkillers, such as paracetamol, ibuprofen or aspirin. Always read the patient information that comes with your medicine and if you have any questions, ask you pharmacist for advice. The pain usually resolves after two to three days.
Some jelly fish are venomous and may sting you if you touch them. If you're stung by a jelly fish, you should wash off any tentacles that are still attached. Apply a cold compress, such as ice or a bag of frozen peas wrapped in a towel, to help reduce any swelling. You shouldn't apply ice directly to your skin as it can damage your skin. You shouldn't use vinegar for treating jelly fish stings in the UK. Instead mix some baking soda in a little water and apply to the affected area.

It's quite common to be bitten or stung by insects. If this happens, you should remove any of the sting still present in the wound by brushing or scraping it off. The edge of a credit card may be useful for this. Don't use tweezers to remove the sting as this pushes more venom into the skin. Apply a cold compress, such as ice or a bag of frozen peas wrapped in a towel, to help reduce swelling. You shouldn't apply ice directly to your skin as it can damage your skin. If your pain and swelling don't go away you should seek medical advice. If you have any problems breathing or swelling to your face, neck, tongue, lips or mouth, you should call for emergency help or go to hospital immediately.

What should I do if I have taken too many paracetamol tablets?

Paracetamol poisoning doesn't always have symptoms. If you or someone you know has taken more than the recommended dose of paracetamol (which is 1g, usually two tablets, every four hours up to a maximum of 4g in 24 hours) you should seek urgent medical attention.


Paracetamol poisoning is the most common form of drug poisoning reported to the National Poisons Information Service.

If you have taken too much paracetamol, you may feel sick or vomit but you may not have any symptoms at all. However, there are severe complications of paracetamol poisoning and if left untreated an overdose can lead to liver and kidney failure and eventually death.

If you, or someone you know, has taken an overdose of paracetamol you should seek medical advice immediately. You should be prepared to provide the following information.

  • How many paracetamol tablets you have taken – give the container or packet(s) to the doctor or nurse if you still have them. It's also important to tell him or her if you have taken them all at once or if the overdose has been taken over a period of time (for example, for pain relief) as this will affect your treatment.
  • When your last paracetamol tablet was taken. The timing of a paracetamol overdose will affect any treatment given.
  • Your age and weight.

If you arrive at hospital within one hour of taking the overdose, you may be given something to drink which will help to prevent your body from absorbing any more of the paracetamol. Your doctor or nurse will need to take a sample of your blood. This is usually taken four hours after the paracetamol overdose.

There is an antidote to treat paracetamol poisoning and if given early it can prevent severe complications. You may need to be admitted to hospital for treatment and monitoring. This will depend on:

  • your medical history
  • your blood results
  • the timing of your paracetamol overdose
  • whether your overdose was taken all at once or over a period of time

If you're admitted to hospital, you will need to stay for around 24 hours and have additional blood tests. You may be allowed to go home following treatment once your doctor is happy with your test results.

What can I do to prevent carbon monoxide poisoning in my home?

Carbon monoxide (CO) is a highly poisonous gas that is produced when certain fuels aren't burnt completely. You should fit CO detectors in your home and make sure that any fuel-burning appliances, such as a gas boiler or wood-burning stove, are serviced annually.


CO is a tasteless, odourless gas that is responsible for more than 20 deaths per year in the UK. CO may be produced by appliances that burn fossil fuels (eg gas, coal and oil) if they aren't working correctly.
Symptoms of CO poisoning include:

  • flu-like symptoms (eg headache, feeling sick)
  • dizziness
  • a feeling of weakness
  • poor concentration

In severe cases you may have:

  • irritability, confusion or memory loss
  • chest pain
  • difficulty breathing
  • seizures (fits)
  • loss of consciousness

There are some simple measures you can take to prevent CO poisoning.

  • Check the pilot light on your gas boiler: it should burn blue. If it's yellow or orange, switch it off and have it checked.
  • Make sure that all your gas appliances are serviced annually by an engineer on the Gas Safe Register. Watch out for signs of staining, soot or discolouration as this may indicate a problem.
  • Make sure that all other fuel-burning appliances are serviced annually by a professional.
  • Fit CO detectors in your home. You should buy a British Standard approved CO detector that has an alarm. These should be maintained and replaced according to the manufacturers' instructions. Spot detectors aren't recommended as they need to be changed every six months and don’t make a sound to alert you. If your alarm goes off, turn off all fuel-burning appliances and open all of your doors and windows. You should call a Gas Safe Registered engineer to check your appliances.

If you think you, or someone you know, are suffering from CO poisoning you should seek urgent medical attention.

Further information

  • Royal Society for the Prevention of Accidents (RoSPA)
  • National Grid Gas Emergency line
    0800 111 999


  • Simon C, Everitt H, van Dorp F. Oxford handbook of general practice. 3rd ed. Oxford: Oxford University Press, 2010: 1112
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  • Carbon monoxide poisoning. Clinical Knowledge Summaries. www.cks.nhs.uk, accessed 10 October 2010
  • List of symbols, abbreviations, risk and safety phrases. Health and Safety Executive. www.hse.gov.uk, accessed 10 October 2010
  • Toxicity, mushroom. eMedicine. www.emedicine.medscape.com, accessed 12 October 2010
  • Swallowed poisons. St John Ambulance. www.sja.org.uk, accessed 18 October 2010
  • Primary Survey. St John’s Ambulance. www.sja.org.uk, accessed 18 October 2010
  • Poisonous plants and fungi. St John’s Ambulance. www.sja.org.uk, accessed 18 October 2010
  • Corneal superficial injury. Clinical Knowledge Summaries. www.cks.nhs.uk, accessed 8 November 2010
  • Basic advice on first aid at work. Health and Safety Executive. www.hse.gov.uk, accessed 8 November 2010
  • Keeping children safe from poisoning. Child accident prevention trust. www.capt.org.uk, accessed 8 November 2010
  • Gas safety in the home. Gas Safe Register. www.gassaferegister.co.uk, accessed 8 November 2010
  • Adder. Forestry Commission. www.forestry.gov.uk, accessed 8 November 2010
  • Insect bites and stings. Clinical Knowledge Summaries. www.cks.nhs.uk, accessed 8 November 2010
  • Poisoning and overdose. Clinical Knowledge Summaries. www.cks.nhs.uk, accessed 8 November 2010
  • Fit a carbon monoxide alarm. Gas safe register. www.gassaferegister.co.uk, accessed 8 November 2010

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