Paracetamol is one of the most commonly used painkillers in the UK – but the NHS has issued a warning about certain medications that should never be taken alongside it
Fiona Callingham Lifestyle writer
15:50, 05 Nov 2025
In rare cases, it’s possible to have a serious allergic reaction (anaphylaxis) to paracetamol(Image: Getty)
The NHS has urged caution when using a widely-available painkiller as it could react dangerously with other medications.
Across the UK, countless people depend on over-the-counter treatments for daily aches and ailments.
Among the pain relief options available, paracetamol stands as one of the most frequently used medicines, typically taken for headaches, back pain and colds amongst other conditions.
Nevertheless, like any medication, using paracetamol carries particular risks.
The NHS has published guidance regarding the safe usage of paracetamol – including which drug combinations must be avoided, reports the Mirror.
“Paracetamol is not suitable for some people,” the health service states.
This encompasses individuals who routinely take warfarin – a medication designed to prevent blood clots.
Should this situation apply to you, you should speak with your GP before using paracetamol, the health service advises.
The NHS explains: “Paracetamol can increase the risk of bleeding if you take it [warfarin] regularly.”
Nevertheless, using small doses of paracetamol alongside warfarin is deemed safe.
The NHS states: “It’s safe to take paracetamol while you’re on warfarin. But take the lowest dose that controls your pain. Taking more than four, 500mg tablets over 24 hours for longer than a few days may make your blood clot more slowly.
“This puts you at risk of bleeding.”
Paracetamol can increase the risk of bleeding if you take it warfarin regularly, according to the NHS(Image: Getty)
It is equally dangerous to combine the painkiller with other treatments containing paracetamol, such as co-codamol or particular cold and flu medicines. This is due to the potential risk of overdose.
Other painkillers such as ibuprofen, aspirin and codeine do not contain paracetamol and can be safely taken alongside it.
The NHS recommends that you should seek advice from your doctor before taking paracetamol if you are on medication for epilepsy or tuberculosis (TB), as this combination could also pose risks.
In general, the NHS states that paracetamol is not affected by herbal remedies or supplements. However, it notes: “There’s not enough information to say whether complementary medicines, herbal remedies and supplements are safe to take with paracetamol.
“They’re not tested in the same way as pharmacy and prescription medicines. They’re generally not tested for the effect they have on other medicines.
“Tell your doctor or pharmacist if you’re taking any other medicines, including herbal remedies, vitamins or supplements.”
A with any medication, taking paracetamol comes with some warnings(Image: getty)
Side effects of paracetamol
Your lips, mouth, throat or tongue suddenly become swollenYou’re breathing very fast or struggling to breathe (you may become very wheezy or feel like you’re choking or gasping for air)Your throat feels tight or you’re struggling to swallowYour skin, tongue or lips turn blue, grey or pale (if you have black or brown skin, this may be easier to see on the palms of your hands or soles of your feet)You suddenly become very confused, drowsy or dizzySomeone faints and cannot be woken upA child is limp, floppy or not responding like they normally do (their head may fall to the side, backwards or forwards, or they may find it difficult to lift their head or focus on your face)
Paracetamol “very rarely” causes side effects when taken at the correct dosage. For a comprehensive list, you should check the information leaflet inside the packaging.
In rare cases, it’s possible to experience a serious allergic reaction (anaphylaxis) to paracetamol. The NHS advises that you should dial 999 immediately if:.
For more information, visit the NHS website here.