7 Signs Of Carbon Monoxide Poisoning | Options Skills
Home » Homeowner Guide » 7 Signs Of Carbon Monoxide Poisoning

7 Signs Of Carbon Monoxide Poisoning

Gas engineer servicing a boiler

Carbon monoxide is a poisonous gas with neither a taste nor smell. Because of this, it can be challenging to recognise when you may be suffering from carbon monoxide poisoning. The symptoms of CO poisoning are also easily mistaken as being caused by something else.

The longer you are exposed to carbon monoxide, the more severe the symptoms are. Fatal if inhaled in large amounts, carbon monoxide poisoning kills around 25 people each year in England and Wales.

CO alarms can detect and alert you to dangerous amounts of carbon monoxide, but even so, it’s essential to recognise the signs and symptoms of poisoning.

Dull Headache

The most common early warning sign of carbon monoxide will present itself as a dull headache. It’s easy to ignore headaches, so pay attention to if they seem to strike in a particular place, e.g. your home, work, etc.


Dizziness is common in the early stages of carbon monoxide poisoning. However, it can also lead to loss of consciousness and fainting.

Nausea or Vomiting

Like headaches and dizziness, vomiting is also an early sign of CO poisoning. It can be noticeable as CO poisoning due to the lack of fever.


A build-up of carbon monoxide can impact a person’s ability to think straight, leading to confusion, memory problems and impaired judgement.

Shortness of Breath

As carbon monoxide poisoning becomes more severe, it can cause shortness of breath or rapid breathing. There may also be a feeling of tightening or pain in the chest area.

Blurred Vision

Common in severe cases of carbon monoxide poisoning, blurred vision occurs as a lack of oxygen affects the brain.


A seizure, defined as “a sudden, uncontrolled electrical disturbance in the brain”, occurs in near-fatal situations. You should seek medical help immediately.

Due to how fatal CO poisoning can be, before letting anyone undertake gas work on your home, you must ensure they’re gas safe registered.

Do what you can to reduce the risk of CO poisoning by installing an alarm on your property and looking after your boiler.

All data correct at time of publication.