Oxygen gas given as a treatment
Medical oxygen
Oxygen gas given as a treatment to correct or prevent low blood-oxygen levels, aimed at a target oxygen level rather than for comfort.
What is Medical oxygen?
Medical oxygen is oxygen gas given as a treatment when the level of oxygen in the blood is too low, or to stop it dropping too low. It is a medicine, not simply something to make people feel better, and it is given to reach a target oxygen level set for that person. In some chronic lung conditions, giving too much oxygen can actually be harmful, so the amount is carefully controlled. A vital safety point is that oxygen strongly supports fire, so no smoking, naked flames or oily substances are allowed near it. It is delivered through masks, nasal prongs or other devices.
Education and reference only. This is a plain-language guide to Medical oxygen — it deliberately contains no doses. Doses depend on the person, the brand and the reason for treatment, and belong with your prescriber. Always check the BNF, the product labelling (SmPC) and follow medical advice.
What it is
Medical oxygen is purified oxygen gas used as a treatment. The air we breathe is only part oxygen, and when illness or injury stops enough oxygen reaching the blood, extra oxygen can be given to make up the difference. It is supplied from cylinders or made on the spot by an oxygen concentrator, and breathed in through a mask, nasal prongs or similar device. It is used in hospitals, ambulances and sometimes at home for people with long-term low oxygen levels. Importantly, it is a prescribed treatment with a target level to aim for, not something to use freely for breathlessness alone.
How it works
By increasing the amount of oxygen in the air a person breathes, medical oxygen helps more oxygen pass into the blood and reach the body's organs, correcting or preventing dangerously low levels. The aim is usually to keep the blood-oxygen level within a target range, which is why it is measured and the flow adjusted to suit. In most people, more oxygen simply raises a low level back to where it should be. In some people with long-standing lung disease, however, giving too much can upset the way they breathe and become harmful, which is why the amount is set carefully and checked rather than turned up freely.
Company & origin
Originated / developed by: Specialist gas suppliers.
A medical gas used throughout the UK to treat or prevent low blood-oxygen levels, supplied as cylinders or from oxygen concentrators.
Practical use
How to take Medical oxygen
General, dose-free guidance — always follow your prescriber's and the leaflet's specific instructions.
- Use it at the flow and with the device you have been prescribed, to reach the target oxygen level set for you.
- Do not turn the oxygen up on your own, as too much can be harmful for some people with lung conditions.
- Never smoke, light a flame or use candles near oxygen, as it strongly supports fire.
- Keep oily or greasy substances, including some skin creams, away from the equipment and your face while using it.
- Look after and store the equipment as instructed, and report any faults or problems.
Weighing it up
Advantages & disadvantages of Medical oxygen
Advantages
- Corrects or prevents dangerously low blood-oxygen levels, which can be life-saving.
- Can be given in hospital, by ambulance or at home depending on the need.
- Delivered in different ways, from nasal prongs to masks, to suit the situation.
Disadvantages
- In some people with long-standing lung disease, too much oxygen can be harmful.
- It strongly supports fire, so strict safety precautions are needed.
- It treats low oxygen levels rather than breathlessness in general, so it is not always the answer to feeling short of breath.
Practical use
Good to know
The most important thing to understand is that oxygen is a treatment aimed at a target level, not a comfort measure: it corrects low blood-oxygen, and feeling breathless does not always mean oxygen is low. In some people with long-standing lung disease, such as some forms of COPD, giving too much oxygen can actually be dangerous by disturbing their breathing, so a specific target range is set and the level is checked rather than the flow simply turned up. The other crucial point is fire safety: oxygen does not burn itself but it strongly supports burning, so smoking, naked flames, candles and oily or greasy substances must be kept well away from oxygen equipment. Home oxygen comes with clear instructions on safe storage and use, and the equipment should be looked after as advised.
Who should not take it / use with caution
- It is not a treatment for breathlessness when blood-oxygen levels are normal.
- People with certain lung conditions need a carefully controlled amount, as too much can be harmful.
- It must not be used near smoking, naked flames or oily substances because of the fire risk.
Monitoring
- Measuring the blood-oxygen level to keep it within the target range.
- Checking that the right device and flow are being used.
- In some lung conditions, occasional blood tests to make sure too much oxygen is not causing harm.
Side effects
- A dry or sore nose, mouth or throat from the gas flow.
- Skin soreness where the mask or prongs sit.
- In some people with lung disease, drowsiness or breathing problems if too much is given.
Key interactions
- It is not a tablet, but the target level is set alongside any lung or breathing treatments you use.
- Some treatments can affect breathing, so the team reviews these together with your oxygen.
- The main hazard is physical, not chemical: oxygen and fire must be kept apart.
Available as: Oxygen gas from cylinders or concentrators, breathed in through masks, nasal prongs or other devices.
Answers
Medical oxygen: frequently asked questions
What is medical oxygen used for?
It is given to treat or prevent low blood-oxygen levels, aiming to keep the oxygen in the blood within a target range set for that person.
Can I turn my oxygen up if I feel breathless?
No. Feeling breathless does not always mean oxygen is low, and in some lung conditions too much oxygen can be harmful, so only use the amount prescribed.
Why is smoking near oxygen so dangerous?
Oxygen strongly supports fire, so smoking, naked flames and candles near oxygen equipment can cause a serious fire and must be avoided.
Is oxygen just for comfort?
No. It is a treatment aimed at correcting low blood-oxygen levels, not simply a comfort measure for breathlessness.
Why is my blood-oxygen checked?
The level is measured so the flow can be adjusted to keep it in the target range, making sure you get enough oxygen without getting too much.
Authoritative sources
- BNF
- NICE CKS
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