Paracetamol (brand names Panado®, Tylenol®, Dafalgan®, Empaped®, Antalgic®, Dolorol®, Napamol®, Painamol®, any many, many others) is such a popular pain killer that it almost became the victim of its own success.
When patients are asked “do you have any pain killers at home?”, they often shrug when answering: “not really, just ordinary Panado”. Lots of people consider it so common that it cannot really be much good. Or is it?
Studies have shown that a single dose of paracetamol is more effective against acute pain (e.g. pain after an injury) than codeine or propoxyfene (which are a weaker type of opioids). Combining it with a pain killer from a different group, the NSAID’s like Voltaren®, makes it even more effective. Actually, the combination of these two different types of painkillers relieves pain better than double the dose of each alone!
Side-effects and complications
One of the main attractions of paracetamol is that it has few side-effects. There is no irritation of the stomach, constipation, dizziness or sleepiness, or interference with blood clotting like with other pain killers. This does not mean that paracetamol can be taken with impunity, because there are possible side-effects, and they can be devastating!
One of them is liver failure, especially when paracetamol is taken on a long-term basis, in too high quantities, or in combination with acute or chronic alcohol abuse. One of our university hospitals recently admitted a 42 year old migraine sufferer, who took paracetamol on a regular basis, and who had now taken 2 gram (four tablets) of paracetamol, with a glass of port wine. Three days later she died from liver failure!
Kidney failure is another rare complication. Whether this is due to the paracetamol alone, or due to the fact that paracetamol is often combined by the manufacturer with other painkillers like aspirin, is still under debate. Fact is, however, that long-term intake of paracetamol can pose a risk for renal failure, which is often irreversible, and might necessitate life-long dialysis or a kidney transplant.
Recently it has been shown that paracetamol in combination with aspirin or other NSAID’s increases the risk of these drugs to do damage to the stomach lining, i.e. gastritis or gastric ulcer.
Paracetamol exerts its effect in the brain, it has a so-called central anti-prostaglandin effect. This is probably also the reason why it is a very good anti-pyretic (meaning it brings fever down).
Paracetamol is safe for the newborn and children, but a dose of 90 mg / kg per day should not be exceeded. Give it in four to five divided doses of 15 – 20 mg each. The traditional commercial preparations contain 120 mg/ 5 ml syrup, so a 10 kg baby should not receive more than 5 – 8 ml per dose, and not more than 30 - 35 ml per day of this preparation. To err on the side of safety, one can decrease the administered amount, but the desired pain relief is then often not obtained.
For adults, the recommended maximum daily dose of 4 gram should not be exceeded. This means maximum 1 gram (2 tablets) every six hours.
Because of the possible serious side-effects, care must be taken against chronic intake of paracetamol. Many manufacturers combine paracetamol with other drugs, like caffeine or meprobamate, intended to make you more alert or more sedated.
Often those cocktail drugs (also popular against flu) are totally illogical, and carry a substantial risk for abuse. Many people are known to always have painkillers on them to just pop one when they feel down or stressed out, and become addicted before they realise it. Remember that the side-effects are few, but can be fatal!
Colds and flu
Paracetamol is an extremely popular medication for common cold and flu. Remember that paracetamol (or any other medication) does not cure you from your cold or flu, it will merely take the symptoms away. This means that you will feel a bit better, but the course of the disease is not quicker!
PAIN - A guide to therapy
Arthritis, Pain and Inflammation
Arthritis Foundation of South Africa
Multiple Sclerosis South Africa
The South African Society of Physiotherapy