Could your painkillers give you an accidental overdose

Taking slightly too much paracetamol day after day can be fatal, researchers at Edinburgh University recently warned, as the damage can build up gradually.

Each year, the average adult swallows more than 300 painkilling pills, according to the British Medical Association. So, are you taking the right type — and the right dose. And what are the risks to watch out for

We asked Boots pharmacist Angela Chalmers for her advice…

From ibuprofen and codeine to aspirin and paracetamol, the average adult swallows more than 300 painkilling pills a year

From ibuprofen and codeine to aspirin and paracetamol, the average adult swallows more than 300 painkilling pills a year


This drug works by blocking some of the body’s production of prostaglandins, substances which act as messengers helping to relay pain messages to the brain. As well as a painkiller, ibuprofen is also useful for temperatures, inflammation and period pain.

That’s because prostaglandins control the thermostat in the brain and trigger fever in response to illness; they also trigger inflammation (by causing blood vessels to dilate) in response to injury, and control muscles and trigger cramps in the uterus during a woman’s period.

BEST FOR: Arthritic pain, pain due to injury, period pain, headaches, muscular pain and tooth ache.

DRAWBACKS: Because prostaglandins also protect the lining of the stomach, ibuprofen should be avoided by anyone who’s had stomach ulcers or internal stomach bleeding. It can also cause indigestion and nausea if taken on an empty stomach.

HOW MUCH SHOULD YOU TAKE Up to two 200mg tablets or one 400mg tablet, up to three times a day.


Like morphine and heroin, codeine is a drug derived from the opium plant – indeed nine codeine tablets would be equal to a dose of morphine.

Because of its potency it is only available in combination with ibuprofen in products such as Nurofen Plus or in combination with paracetamol in products such as Co-codamol when bought over the counter.

Rather than working on the cause of the pain, it reduces the perception of pain. It does this by blocking receptors in the spinal cord and the brain which help to send pain signals to the brain.

BEST FOR: Short-term moderate pain, such as one-off really bad back ache or dental pain.

DRAWBACKS: Codeine has a sedative effect so it can make you feel drowsy and like any opium-based drugs can be addictive. The long-term use of codeine can trigger medication-overuse headaches.

Codeine can also cause constipation (it is sometimes used to treat diarrhoea.)

HOW MUCH SHOULD YOU TAKE The maximum you should take in a day is 240mg, although to get this amount you would have be taking prescription-only codeine. Over-the-counter codeine is always combined with another painkiller, and you must stick to the dosage to avoid overdosing with paracetamol or ibuprofen.

PARACETAMOL Paracetamol is gentler on the stomach, so it can be taken on an empty stomach

Paracetamol is gentler on the stomach, so it can be taken on an empty stomach

Like ibuprofen, this blocks the production of prostaglandins but does nothing at the site of the pain to reduce inflammation.

BEST FOR: When you need something to ease aches and pains but you don’t feel like eating — such as when you have a cold or flu. Paracetamol is gentler on the stomach, so unlike ibuprofen or codeine, for example, it can be taken on an empty stomach.

It is the only painkiller suitable for use during pregnancy, and the junior versions such as Calpol can also be given to children over the age of two months.

DRAWBACKS: It is easy to overdose unintentionally, which can lead to liver damage and potentially death.

HOW MUCH SHOULD YOU TAKE The normal dose is two 500mg tablets every four hours, but an adult should take no more than eight tablets in any 24-hour period.

You must also ensure when taking paracetamol with something else, such as a cold remedy that also contains paracetamol, you do not accidentally take too much.


Originally derived from willow bark, aspirin — like ibuprofen — acts on prostaglandins to relieve pain. However, it has another, different effect on these substances.

As well as causing pain, prostaglandins cause platelets in the blood to clump together — this can trigger the formation of a clot, which can cause a heart attack or stroke.

Aspirin can reduce this clotting effect, thereby thinning the blood — which is why it’s often taken at a low, daily preventative dose of 75mg by those who have had a heart attack.

BEST FOR: The same as ibuprofen.

DRAWBACKS: Like ibuprofen, this should not be taken on an empty stomach because it may trigger stomach ulcers.

Also, because it thins the blood, it is best avoided by those on blood-thinning medication, such as warfarin, or anyone with an allergy to aspirin.

HOW MUCH SHOULD YOU TAKE A typical tablet is 300mg, which can be taken up to four times within 24 hours.