Carboxyhaemoglobin
Private Carboxyhaemoglobin blood test in London for £129, measuring one carbon monoxide exposure biomarker with results in around 1 week.
Turnaround time
1 week
Biomarkers count
1
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Overview of the Carboxyhaemoglobin
The Carboxyhaemoglobin blood test is a specialist investigation that measures the proportion of haemoglobin in the blood bound to carbon monoxide, commonly reported as carboxyhaemoglobin or COHb.
Carbon monoxide is a colourless and odourless gas produced when carbon-containing fuels do not burn completely. Potential sources include faulty boilers, gas heaters, fires, wood-burning appliances, vehicle exhaust fumes, generators and other combustion processes.
After carbon monoxide is inhaled, it enters the bloodstream through the lungs and binds strongly to haemoglobin. The resulting compound is called carboxyhaemoglobin.
Haemoglobin normally transports oxygen from the lungs to tissues throughout the body. Carbon monoxide occupies haemoglobin binding sites and also alters the release of oxygen from the remaining sites, potentially reducing effective oxygen delivery to tissues.
The test contains 1 biomarker: Carboxyhaemoglobin. It may be used to provide laboratory evidence of recent carbon monoxide exposure, although the timing of sample collection is particularly important.
Carboxyhaemoglobin concentrations begin to fall once a person leaves the source of exposure. Supplemental oxygen accelerates this process further, meaning a delayed blood sample may show a substantially lower concentration than was present during the exposure.
Smoking also increases baseline carboxyhaemoglobin levels and should be considered when results are interpreted.
This test is not intended to replace emergency assessment of suspected acute carbon monoxide poisoning. Current significant exposure or symptoms such as severe headache, confusion, chest pain, breathlessness, collapse or loss of consciousness require urgent medical care rather than waiting for a routine private blood test result.
What Does the Carboxyhaemoglobin Test Check?
This test measures 1 biomarker.
Carboxyhaemoglobin
Measures the proportion of haemoglobin bound to carbon monoxide. Elevated concentrations may indicate recent carbon monoxide exposure, although smoking status, time since exposure, oxygen treatment and clinical symptoms must all be considered when interpreting the result.
Who May Benefit From the Carboxyhaemoglobin Test?
This test may be suitable for people requiring biochemical assessment of possible recent carbon monoxide exposure, particularly where the suspected exposure has already ended and urgent medical treatment is not required.
Suspected recent carbon monoxide exposure - Carboxyhaemoglobin measurement can provide laboratory evidence that carbon monoxide has entered the bloodstream.
Possible exposure from a faulty boiler or heater - Defective or poorly ventilated fuel-burning appliances can produce carbon monoxide through incomplete combustion.
Smoke or fire exposure - Inhalation of combustion products can result in carbon monoxide entering the bloodstream.
Vehicle or engine exhaust exposure - Carbon monoxide can accumulate when petrol or other combustion engines are operated in enclosed or poorly ventilated environments.
Occupational carbon monoxide exposure - Certain jobs involving combustion equipment, engines or enclosed environments may create a recognised risk of exposure.
Symptoms that occur mainly in one building - Recurrent headache, dizziness or nausea that improves after leaving a property can raise concern about an environmental carbon monoxide source.
Several people experiencing similar symptoms in the same environment - A cluster of unexplained symptoms affecting household members or colleagues may strengthen suspicion of environmental exposure.
Smokers undergoing clinically indicated assessment - Smoking raises baseline carboxyhaemoglobin concentrations and should be documented when testing is performed.
Specialist-requested exposure testing - The test can be arranged privately where a GP, occupational health clinician or other healthcare professional has specifically requested carboxyhaemoglobin measurement.
How to Prepare
Do not deliberately recreate or prolong exposure in an attempt to obtain a higher carboxyhaemoglobin result. If a source of carbon monoxide is suspected, avoid the environment until it has been appropriately assessed.
This test is highly dependent on timing. Where exposure has been recent and symptoms are present, urgent clinical assessment is more appropriate than delaying care to arrange routine private testing.
Symptoms and Reasons to Consider the Carboxyhaemoglobin Test
You may wish to consider the Carboxyhaemoglobin test where previous carbon monoxide exposure is being investigated. Acute or ongoing exposure with significant symptoms requires urgent medical assessment instead of routine private testing.
Headache - Headache is one of the most frequently reported symptoms of carbon monoxide exposure but is highly non-specific.
Dizziness or light-headedness - Reduced effective oxygen delivery can contribute to dizziness, poor balance or feeling faint.
Nausea or vomiting - Gastrointestinal symptoms can occur during carbon monoxide exposure and may resemble viral illness or food-related symptoms.
Unexplained weakness or marked fatigue - Carbon monoxide exposure can interfere with oxygen delivery and contribute to unusual tiredness or weakness.
Difficulty concentrating - Cognitive slowing, poor concentration or confusion can occur with more significant exposure.
Shortness of breath - Breathlessness can occur and may be particularly important in people with underlying heart or lung disease.
Chest pain - Carbon monoxide places additional strain on the cardiovascular system, making chest pain a potentially serious symptom.
Collapse or loss of consciousness - Severe carbon monoxide exposure can cause syncope, seizures, coma and other life-threatening complications.
Symptoms affecting several people or pets in the same building - Similar unexplained symptoms occurring in multiple occupants may indicate a shared environmental source.
Carbon monoxide poisoning can be difficult to recognise because early symptoms overlap with migraine, viral illness, fatigue and many other common conditions. The surrounding circumstances therefore matter considerably.
Carboxyhaemoglobin testing is time-sensitive. Levels fall after exposure ends, so a normal or modest result obtained several hours later does not always exclude clinically important earlier exposure.
If carbon monoxide exposure may still be occurring, leave the suspected environment where it is safe to do so. Severe headache, confusion, chest pain, breathlessness, collapse, seizures, marked drowsiness or loss of consciousness require immediate medical assessment rather than waiting for routine private results.
How to Book Your Carboxyhaemoglobin Test
Booking your Carboxyhaemoglobin test with London Blood Tests is simple, although recent suspected carbon monoxide exposure should be considered carefully before routine testing is arranged.
Choose the Carboxyhaemoglobin
Select the Carboxyhaemoglobin test online and review the important information regarding recent carbon monoxide exposure before booking.
Select your sample collection option
Choose an in-clinic blood draw (+£35) or a home or hotel phlebotomy visit (+£60) where appropriate. Acute symptomatic exposure should be assessed urgently rather than through routine sample collection.
Attend your appointment
A trained professional will collect the required blood sample safely and efficiently at the clinic or during your arranged home or hotel visit.
Laboratory analysis
Your sample is sent to the laboratory, where carboxyhaemoglobin is measured using specialist haematology analysis.
Receive your results securely
Your results are sent securely by email, ready to review yourself or discuss with a GP, occupational health clinician or other suitably qualified healthcare professional.
When Will I Receive My Results?
The expected turnaround time for the Carboxyhaemoglobin test is approximately 1 week after your sample arrives at the laboratory.
Results are sent securely by email once specialist laboratory analysis and authorisation are complete. Turnaround therefore begins when the laboratory receives the sample rather than necessarily from the time your blood is collected.
The reporting turnaround should not be confused with the timing required for diagnosis of acute carbon monoxide poisoning. Where recent exposure and symptoms are present, clinical assessment and appropriate blood sampling should take place urgently.
Understanding Your Results
Your Carboxyhaemoglobin result indicates the proportion of haemoglobin bound to carbon monoxide according to the laboratory method used, commonly reported as a percentage of total haemoglobin.
Small amounts of carboxyhaemoglobin can be detected in people without known poisoning because carbon monoxide is produced in small quantities naturally within the body and can also be encountered through environmental exposure.
Smoking can significantly increase baseline carboxyhaemoglobin concentrations. For this reason, smoking status is an important part of interpreting the result.
An elevated result can support evidence of recent carbon monoxide exposure.
However, the measured level does not necessarily represent the concentration that was present at the time symptoms were at their worst.
Once exposure stops, carbon monoxide progressively leaves haemoglobin. The concentration therefore falls with time. Supplemental oxygen speeds this process substantially.
A delayed sample can consequently produce a relatively low carboxyhaemoglobin result even after clinically important earlier exposure.
The severity of symptoms also does not always correlate closely with a single measured carboxyhaemoglobin concentration. Age, underlying cardiovascular disease, pregnancy, duration of exposure and other individual factors can influence clinical effects.
A result should therefore be interpreted alongside the timing and duration of exposure, smoking status, oxygen treatment, symptoms and the suspected source.
A low or normal result should not be used alone to dismiss a convincing history of significant carbon monoxide exposure, particularly where several hours have elapsed before blood collection.
Why Book With London Blood Tests?
Private carboxyhaemoglobin testing in London - Access specialist Carboxyhaemoglobin testing through London Blood Tests.
Targeted carbon monoxide exposure marker - Measure carboxyhaemoglobin independently when recent carbon monoxide exposure requires laboratory assessment.
Useful after suspected environmental exposure - Testing can provide supporting information following potential exposure from boilers, fires, engines or other combustion sources.
Relevant to occupational exposure assessment - Carboxyhaemoglobin can provide useful biochemical information where carbon monoxide exposure may have occurred at work.
Specialist laboratory analysis - Your sample is processed using dedicated laboratory methods for carboxyhaemoglobin measurement.
Clinic and home visit options - Where clinically appropriate, choose an in-clinic blood draw or arrange home or hotel phlebotomy depending on location and availability.
Secure results by email - Receive your authorised laboratory result securely once analysis is complete.
Clear pricing before booking - The Carboxyhaemoglobin test is priced at £129, with sample collection charges shown separately.
Clear acute-exposure guidance - Information is provided to distinguish routine private testing from situations requiring urgent medical assessment.
Private Carboxyhaemoglobin Blood Test in London
London Blood Tests provides the Carboxyhaemoglobin blood test in London for people requiring specialist laboratory assessment of possible recent carbon monoxide exposure.
The test costs £129 and measures one biomarker: Carboxyhaemoglobin. This represents haemoglobin that has bound to carbon monoxide rather than carrying oxygen normally.
Testing may be relevant following suspected exposure to faulty heating equipment, smoke, vehicle exhaust fumes or other combustion sources. Smoking status, timing of blood collection and any oxygen treatment are important because each can materially influence the measured result.
Clinic appointments are available alongside home and hotel phlebotomy where clinically appropriate, providing flexible options for people looking for a private Carboxyhaemoglobin blood test in London.
This service should not be used to delay emergency treatment. Recent or ongoing suspected exposure accompanied by significant symptoms requires prompt medical assessment because carboxyhaemoglobin concentrations fall after exposure ends and acute carbon monoxide poisoning can be life-threatening.